U.S. patent application number 13/285301 was filed with the patent office on 2012-03-01 for multilayer articles comprising resorcinol arylate polyester and method for making thereof.
This patent application is currently assigned to SABIC Innovative Plastics IP B.V.. Invention is credited to Himanshu Asthana, Gert Boven, Beth Brister, Hendrik Cornelus Jacobus de Nooijer, Axel Grimm, Enamul Haque, Chris Hartshorn, Christopher L. Hein, Edward Kung, Xiangyang Li, David Rosendale, Luca Saggese, Paul Sybert, Safwat Tadros, Erich O. Teutsch, Theodorus J.M. Timmerman, Glen Tryson, Jeroen Vervoort, Hua Wang, Hongyi Zhou.
Application Number | 20120052314 13/285301 |
Document ID | / |
Family ID | 26905478 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120052314 |
Kind Code |
A1 |
Asthana; Himanshu ; et
al. |
March 1, 2012 |
MULTILAYER ARTICLES COMPRISING RESORCINOL ARYLATE POLYESTER AND
METHOD FOR MAKING THEREOF
Abstract
Multilayer articles comprising a coating layer comprising
resorcinol arylate chain members bound to a support substrate via
an optional intermediate tie layer. Adhesion between the layers of
the multilayer article is enhanced by modifying at least a part of
a surface of at least one of the layers in the multilayer article
by a technique selected from at least one of: surface adhesive
treatment, surface corona treatment, flame treatment, plasma
surface treatment, vacuum deposition treatment, ionization
radiation, chemical surface treatment, surface abrasion treatment,
and surface texturing treating.
Inventors: |
Asthana; Himanshu;
(Evansville, IN) ; Tadros; Safwat; (Evansville,
IN) ; Sybert; Paul; (Evansville, IN) ; Hein;
Christopher L.; (Evansville, IN) ; Kung; Edward;
(Evansville, IN) ; Rosendale; David; (Mount
Vernon, IN) ; Li; Xiangyang; (Mount Vernon, IN)
; Saggese; Luca; (Pittsfield, MA) ; Teutsch; Erich
O.; (Richmond, MA) ; Tryson; Glen; (Malden
Bridge, NY) ; Wang; Hua; (Clifton Park, NY) ;
Zhou; Hongyi; (Niskayuna, NY) ; Hartshorn; Chris;
(Schenectady, NY) ; Grimm; Axel; (Bergen op Zoom,
NL) ; Timmerman; Theodorus J.M.; (Hoogerheide,
NL) ; Vervoort; Jeroen; (Bergen op Zoom, NL) ;
de Nooijer; Hendrik Cornelus Jacobus; (Middelburg, NL)
; Boven; Gert; (Steenbergen, NL) ; Brister;
Beth; (Bergen op Zoom, NL) ; Haque; Enamul;
(Novi, MI) |
Assignee: |
SABIC Innovative Plastics IP
B.V.
Bergen op Zoom
NL
|
Family ID: |
26905478 |
Appl. No.: |
13/285301 |
Filed: |
October 31, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10210746 |
Jul 31, 2002 |
8057903 |
|
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13285301 |
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60334513 |
Nov 30, 2001 |
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Current U.S.
Class: |
428/458 ;
156/272.6; 156/306.6; 156/306.9; 264/177.1; 264/279; 264/319;
264/400; 428/480 |
Current CPC
Class: |
B32B 38/12 20130101;
B29C 48/08 20190201; Y10T 428/24942 20150115; B29C 48/21 20190201;
B32B 27/06 20130101; B32B 2605/08 20130101; Y10T 428/31565
20150401; Y10T 428/31681 20150401; Y10T 428/3158 20150401; B29K
2995/0055 20130101; Y10T 428/31587 20150401; B32B 37/153 20130101;
B32B 38/0008 20130101; B29K 2705/00 20130101; B29C 48/307 20190201;
B29K 2995/0058 20130101; B29L 2031/3008 20130101; B32B 27/36
20130101; B32B 2038/0016 20130101; B32B 2310/0445 20130101; B29C
51/02 20130101; B29K 2033/04 20130101; B32B 2310/14 20130101; B29K
2633/08 20130101; B29C 45/14811 20130101; B29C 51/082 20130101;
B29C 48/495 20190201; B29L 2031/30 20130101; Y10T 428/31786
20150401; Y10T 428/31507 20150401; B29K 2713/00 20130101; B29C
48/0017 20190201; B29C 51/002 20130101; B29C 2791/001 20130101 |
Class at
Publication: |
428/458 ;
264/279; 264/177.1; 156/306.6; 156/306.9; 264/319; 156/272.6;
264/400; 428/480 |
International
Class: |
B32B 27/18 20060101
B32B027/18; B29C 47/06 20060101 B29C047/06; B32B 27/36 20060101
B32B027/36; B29C 51/14 20060101 B29C051/14; B29C 65/02 20060101
B29C065/02; B29C 35/08 20060101 B29C035/08; B29C 45/14 20060101
B29C045/14; C09J 5/06 20060101 C09J005/06 |
Claims
1. A process for forming a shaped article by forming a layer of a
first thermoplastic resin adjacent second resin to form a
composite, said first layer comprising an arylate polyester polymer
and said second resin comprises a thermoformable resin, and
thermoforming said composite into said shaped article.
2. A method of making an article having a weatherable outer surface
with a high quality finish appearance, comprising: shaping an outer
layer comprising resorcinol arylate polyester chain members into a
three-dimensional shape in a vacuum-forming apparatus; placing said
three-dimensional shape in a cavity of an injection molding
apparatus; and injecting a flowable resin into the cavity of said
injection molding apparatus behind said layer comprising resorcinol
arylate polyester chain members to form a multi-layer article.
3. The method of claim 2, wherein said flowable resin is selected
from the group consisting of an aromatic polycarbonate resin, an
ABS resin, an ASA resin, a polyester, a polyphenylene ether, a
polyphenylene ether/polystyrene blend, a copolyestercarbonate, a
poly(aklyne dixarboxylate), polyamide, a TPO, or blends
thereof.
4. The method of claim 2, wherein said outer layer comprising
resorcinol arylate polyester chain members further comprises an
adherent layer on a surface of said outer layer, and wherein said
flowable resin is injected into the cavity of said injection
molding apparatus behind said adherent layer.
5. The method of claim 2, wherein said outer layer is made by
coextruding a material comprising resorcinol arylate polyester
chain members and a material selected from the group consisting of
an aromatic polycarbonate resin, an ABS resin, an ASA resin, a
polyester, a polyphenylene ether, a polyphenylene ether/polystyrene
blend, a copolyestercarbonate, a poly(aklyne dixarboxylate),
polyamide, or blends thereof.
6. The method of claim 2, wherein said outer layer comprising
resorcinol arylate polyester chain members further comprises a
colored adherent layer on a surface of said outer layer and wherein
said flowable resin is injected into the cavity of said injection
molding apparatus behind said colored adherent layer, thereby said
colored adherent layer imparts color appearance on the surface of
the article having a weatherable outer surface.
7. An article produced in accordance with the method of claim
2.
8. An article having a weatherable outer surface with a high
quality finish appearance, said article is produced by the
following method: thermoforming an outer layer comprising
resorcinol arylate polyester chain members into a three-dimensional
shape in a vacuum-forming apparatus; placing said three-dimensional
shape in a cavity of an injection molding apparatus; and injecting
a flowable resin into the cavity of said injection molding
apparatus behind said layer comprising resorcinol arylate polyester
chain members to form a multi-layer article.
9. A method for producing an article having a weatherable outer
surface with a high quality finish appearance, said method
comprising: laminating an outer layer onto a metal substrate
forming a laminate composite, wherein the outer layer comprises
resorcinol arylate polyester chain members; thermoforming said
laminate composite into a three-dimensional shape in a
vacuum-forming apparatus; placing said three-dimensional shape in a
cavity of an injection molding apparatus; and injecting a flowable
resin into the cavity of said injection molding apparatus behind
said metal substrate of said thermoformed laminate composite to
form a multi-layer article.
10. The method of claim 9, wherein said metal substrate is a chrome
foil or Al foil.
11. An article produced in accordance with the method of claim
9.
12. In a coextrusion process for preparing a composite polymer film
construction having at least two layers wherein the polymers in the
layers are fusion-bonded to each other and wherein: a) polymer
resins forming said layers are fed into separate channels of a film
die as separate streams, b) the polymer streams flow into the film
die and are extruded to form an extrudate in which the polymer
streams form a film having fusion-bonded layers, the improvement
consists of employing resorcinol arylate polyester chain members to
form a surface layer of said polymer film construction.
13. The coextrusion process of claim 11, wherein said surface layer
comprising resorcinol arylate polyester chain members is fusion
bonded to an adherent layer comprising a material selected from the
group consisting of an aromatic polycarbonate resin, an ABS resin,
an ASA resin, a polyester, a polyphenylene ether, a polyphenylene
ether/polystyrene blend, a copolyestercarbonate, a poly(aklyne
dixarboxylate), polyamide, or blends thereof.
14. In an adhesive method for bonding together surfaces of a first
layer and second layer, in which method a hot melt adhesive heated
above its melting point is placed between the surfaces to be bonded
together, said surfaces are assembled together and the assembly is
cooled to ambient temperature to solidify such adhesive; the
improvement which comprises: fabricating said first layer from a
resin comprising resorcinol arylate polyester chain members, and
fabricating said second layer from paper, metal, fabric, or a resin
selected an aromatic polycarbonate resin, an ABS resin, an ASA
resin, a polyester, a polyphenylene ether, a polyphenylene
ether/polystyrene blend, a copolyestercarbonate, a poly(aklyne
dixarboxylate), polyamide, or blends thereof.
15. A method for forming a multilayer article, said method
comprising the step of: tacking a first layer onto a second layer
by bringing the respective films into contacting array, wherein the
first layer comprises resorcinol arylate polyester chain members,
and wherein the second layer comprises at least one of a
thermoplastic polycarbonate, a thermoplastic polyester, a
polyolefin, a polyamide, a polyacrylonitrile, a polystyrene, a
polyvinyl chloride; forming a continuous strip of laminated joint
film; and subjecting said continuous strip of laminated joint film
to sufficient heat and pressure for bonding and thermofusing the
first layer and second layer of said laminated joint film, forming
a substantially fully fused laminated joint film.
16. The method of claim 15, wherein at least one of said first film
layer and second film layer includes a tie-layer on a surface, for
contacting with a surface of another of said film layer to
facilitate tacking said film layers together.
17. The method of claim 15, wherein the tie-layer comprises
polyurethane.
18. The method of claim 15, wherein an adhesion of the tie-layer to
the substrate layer provides a ninety-degree peel force of at least
1,750 Newtons per meter.
19. The method of claim 15, wherein at least a part of a surface of
at least one of said first and second layers is modified by a
technique selected from at least one of: surface adhesive
treatment, surface corona treatment, flame treatment, plasma
surface treatment, vacuum deposition treatment, ionization
radiation, chemical surface treatment, surface abrasion treatment,
and surface texturing treating.
20. A coextrusion process, wherein said surface layer comprising of
resorcinol arylate polyester chain members is fusion bonded to an
adherent 2.sup.nd layer comprising a material selected from the
group consisting of an aromatic polycarbonate resin,
copolyestercarbonate, a poly(aklyne dicarboxylate), a resorcinol
arylate polyester, a polyresorcinol arylate BPA carbonate
copolymer, PMMA or blends thereof and, wherein said 2.sup.nd
adherent layer is fusion bonded to a 3.sup.rd layer comprising of a
material selected from the group selected from an aromatic
polycarbonate resin, copolyestercarbonate, a poly(aklyne
dicarboxylate), a resorcinol arylate polyester, a polyresorcinol
arylate BPA carbonate copolymer, PMMA, or blends thereof and
3.sup.rd layer is bonded to a tie layer.
21. The coextrusion process of claim 20, wherein said surface layer
comprising of resorcinol arylate polyester chain members is fusion
bonded to an adherent 2.sup.nd layer comprising a material selected
from the group consisting of an aromatic polycarbonate resin,
copolyestercarbonate, a poly(aklyne dicarboxylate), a resorcinol
arylate polyester, a polyresorcinol arylate BPA carbonate
copolymer, PMMA, or blends thereof and said 2.sup.nd adherent layer
is fusion bonded to a 3.sup.rd layer comprising of a material
selected from the group selected from an aromatic polycarbonate
resin, copolyestercarbonate, a poly(aklyne dicarboxylate), a
resorcinol arylate polyester, a polyresorcinol arylate BPA
carbonate copolymer, PMMA, or blends thereof.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent
application Ser. No. 10/210,746 filed Jul. 31, 2002, which is
related to and claims priority from Provisional Application No.
60/334,513 filed on Nov. 30, 2001, the entire contents of each are
incorporated by reference herein.
FIELD OF THE INVENTION
[0002] This invention relates to articles having a coating layer
comprising resorcinol arylate polyester chain members, and a method
for preparation the multilayer articles.
BACKGROUND OF THE INVENTION
[0003] Compositions and weatherable multilayer articles comprising
resorcinol arylate chain members are known. See Published Patent
Application Nos. EP 1124878 and WO0069945. The prior art references
generally discuss methods to manufacture multilayer articles by
various processes including co-injection molding, coextrusion,
overmolding, multi-shot injection molding, sheet molding and
placement of a film of the coating layer material on the surface of
a substrate layer optionally followed by adhesion of the two layers
by a tie-layer, with the coating layer comprising resorcinol
arylate polyester chain members. In some applications, the
multilayer article as taught in the prior art may be separated into
the constituent substrate layer and the coating layer comprising
resorcinol arylate chain members. If applied onto a substrate,
i.e., wood, metal, plastic, paper, etc. as a protective
carrier/weatherable layer, the inter-layers or intra-layers in the
prior art may undergo separation.
[0004] Thermoset plastics are commonly used for automotive body
panels including appearance parts, having to undergo extensive
surface preparation to provide a weatherable, smooth, glossy
surface, which always requires a coating of some type. Producing
the desired surface is expensive and time consuming and detracts
from the excellent mechanical properties of the thermoset
materials. Without the proper finishing work a painted surface will
not meet the automotive class "A" requirements due to imperfections
in the surface from exposed glass fibers, glass fiber
"read-through," "paint popping," long and short term waviness,
"orange peel," and variations in gloss. Overmolding of thin,
preformed paint films is also possible, but only for compositions
that are capable of being molded to provide nearly perfect surfaces
without secondary operations. The as-molded surface quality has
been improved considerably over the last few years, but all parts
to be painted still have to be sanded, especially at the edges, and
sealed and primed prior to painting. In-mold coating can obviate
these operations, but only at the cost of greatly increased cycle
time and cost. The process uses expensive paint systems that may be
applied to the part surface while the mold is re-opened slightly,
then closed to distribute and cure the coating. Surface
improvements have also been obtained by the addition of low profile
additives. Such additives reduce the "read-through" at the surface
by causing minute internal voids due to the high stresses in the
resin as it shrinks due to polymerization and differential
shrinkage of the glass and resin as the part cools. The voiding of
the additive relieves the stresses and provides a smoother surface.
If the void occurs at the surface however, a defect may result in
the finish. The voids also act as stress concentrators, which may
cause premature failures under additional stress or appear during
the general sanding at the surface and leave a pit that the
painting process can't hide.
[0005] One alternate approach in the prior art is to adhere a thin,
high quality surface film to the molded part during or after the
molding operation, also known as in-mold decorating or
over-molding. Such films are generally highly crosslinked films
based on acrylics or fluoropolymer films, which are very expensive
and need special adhesive layers, adding cost and additional
sources for defects and failure. The films are generally thin due
to the expense of the fluoropolymer, or brittleness if acrylic and
their method of production. The thin layers also make it difficult
to maintain a uniform color when the film is non-uniformly
stretched to conform to the part.
[0006] Applicants have found that substrate comprising resorcinol
arylate chain members may be used as a weatherable surface with
high gloss and hardness, providing a class "A" finish in thermoset
molding, for use in automotive parts. Applicants have also found
that the use of certain tie-layers surprisingly increase the
adhesion between layers of a multilayer article, with a coating
layer comprising resorcinol arylate chain members and the substrate
layer, or the adhesion between the multilayer article comprising a
coating layer of resorcinol arylate chain members and a substrate
layer with another surface. We have also found that the adhesion
between the layers can be significantly improved by various surface
modification methods, by modifying the surface of at least one of
the layers in a multilayer article.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIGS. 1(A), (B), and (C) are schematic section views
respectively illustrating examples of a multilayer article obtained
in accordance with the present invention.
[0008] FIG. 2 is a schematic view illustrating of a method of
manufacturing a multilayer article in accordance with one
embodiment of the invention.
[0009] FIG. 3 is a schematic view illustrating of a method of
manufacturing the multilayer article in accordance with one
embodiment of the invention via the co-extrusion process.
[0010] FIG. 4 is a schematic view illustrating a method of applying
a masking layer to the multilayer article of the present
invention.
DESCRIPTION OF THE INVENTION
[0011] The instant invention is for an article having an
surface/coating layer comprising resorcinol arylate polyester chain
members. In one embodiment, the article is a multilayer structure
with the coating layer comprising resorcinol arylate polyester
chain members. The instant structure displays good adhesion
properties, good mechanical properties, weatherability, and UV
resistance.
Coating/Weatherable Layer Comprising Resorcinol Arylate Polyester
Chain Members
[0012] The outer layer of the article of the present invention is
comprised of arylate polyester chain members. Said chain members
comprise at least one diphenol residue in combination with at least
one dicarboxylic acid residue.
[0013] Suitable dicarboxylic acid residues include aromatic
dicarboxylic acid residues derived from monocyclic moieties,
preferably isophthalic acid, terephthalic acid, or mixtures of
isophthalic and terephthalic acids, or from polycyclic moieties,
including diphenyl dicarboxylic acid, diphenylether dicarboxylic
acid, naphthalenedicarboxylic acid such as
naphthalene-2,6-dicarboxylic acid. In one embodiment, the
dicarboxylic acid is 1,4-cyclohexanedicarboxylic acid.
[0014] In one embodiment, the diphenol residue is derived from a
1,3-dihydroxybenzene moiety, as illustrated in Formula 1, commonly
referred to as resorcinol or resorcinol moiety.
##STR00001##
[0015] In Formula I, R is at least one of C.sub.1-12 alkyl or
halogen, and n is 0-3. Examples of Resorcinol or resorcinol moiety
includes both unsubstituted 1,3-dihydroxybenzene and substituted
1,3-dihydroxybenzenes.
[0016] In one embodiment, the aromatic dicarboxylic acid residues
are derived from mixtures of isophthalic and/or terephthalic acids
(ITR) as typically illustrated in Formula II.
##STR00002##
[0017] In one embodiment of the laminated structure, the outer
layer or the coating layer comprises resorcinol arylate polyester
chain members as illustrated in Formula III wherein R and n are as
previously defined:
##STR00003##
[0018] In one embodiment, the outer layer is a blend of polymers
comprising resorcinol arylate polyester chain members and at least
one other polymer selected from at least one of miscible,
immiscible, and compatibilized blends including but not limited to:
polycarbonates, polyesters, polyetherimides, polyphenylene ethers,
PC/ABS, PC/ASA, PC/PBT, PC/PET, PC/polyetherimide, polyamide,
polyester/polyetherimide, polyphenylene ether/polystyrene,
polyphenylene ether/polyamide, polyphenylene ether/polyester,
blends, regrinds and foams of any of the above. In another
embodiment, the outer layer is comprised of a block
copolyestercarbonate comprising resorcinol arylate-containing block
segments in combination with organic carbonate block segments as
disclosed in Patent Application EP 1124878.
[0019] In one embodiment of applications wherein high levels of
scratch and/or chemical resistance are required, the amount of
resorcinol arylate-containing block segments is in the range of
about 50 to 100 mole %. In other embodiments with a lesser
requirement for scratch and chemical resistance, the level is about
20 to 50 mole percent.
[0020] The composition may additionally contain art-recognized
additives including but not limited to metal flakes, pigments,
dyes, impact modifiers, UV screeners, flame retardants, fillers,
stabilizers, flow aids, ester interchange inhibitors, and mold
release agents. Pigments include both clear pigments such as
inorganic siliceous pigments (silica pigments for example) and
conventional pigments used in coating compositions. In one
preferred embodiment, the weatherable coating layer is a clear
layer with no pigment or dye in the composition.
[0021] The weatherable coating layer may be produced as a separate
layer, followed by application to a second layer of the multilayer
article of the present invention. It can also be produced by
simultaneous productions of the layers in a production process.
Thus, the weatherable coating layer may be produced and employed in
such methods but not limited to molding, extrusion, co-injection
molding, co-extrusion, overmolding, coating, and the placement of
the layer onto the surface of a second layer.
[0022] In one embodiment, the weatherable coating layer is placed
or "coated" onto the surface of a second layer via a coating
process. The coating process may include but not limited to a
fluidizing process involving a fluidized bed of powered ITR, for
the substrate or article bearing the substrate to be coated with
the weatherable layer containing ITR. In another embodiment, the
ITR is dissolved in a fugitive solvent, and the weatherable layer
is used to "coat" a second layer or a substrate by various
well-known coating means, including but not limited to dipping,
spraying, rolling, dipping, flow-coating, or combinations thereof.
Fugitive solvents are meant to include solvents or other liquids
that evaporate and leaves the weatherable coating containing
arylate polyester chain members behind after the weatherable
coating layer has been deposited on the substrate. Examples of
fugitive solvents include but not limited to, 1,3-dioxolane,
1,3-dioxane, 1,4-dioxane, tetrahydrofuran, y-butyrolactone,
acetonitrile, dimethyl formamide, methylene chloride chloroform,
chlorobenzene or mixtures of these solvents. The fugitive solvents
may optionally contain stabilizers and/or surfactants. Surfactants
are surface-active compounds including protective colloids,
dispersants, etc. Examples of such surfactants are polyalkylene
oxides, alkyl and aryl sulfonates, quaternary ammonium salts,
alkyl, aryl or ether sulfates, polyvinyl alcohols, partly
hydrolyzed polyvinyl acetates, polyvinyl pyrrolidone, olefin/maleic
anhydride copolymers, formaldehyde condensates, formaldehyde
condensates and alkoxylated phenol/formaldehyde condensates.
[0023] In one embodiment, wherein the second layer or substrate is
coated with a layer containing resorcinol arylate polyester chain
members in a coating application, the thickness of the layer
containing arylate polyester chain members is from 0.1 .mu.m to 5
.mu.m. In other applications, particularly non-coating
applications, the weatherable coating layer is between 0.5 and 150
mils thick (1 mil is 1/1000 inch).
Substrate Layer
[0024] In one embodiment of the invention, the article comprises a
substrate which functions as a support layer or a "colored" layer.
The substrate includes but not is limited to one of a film layer or
layers, a sheet layer or layers, a multi-wall sheet ("MWS"), a
molded polymer substrate, a pre-formed metal substrate or
combinations thereof, with the outer weatherable layer comprising
resorcinol arylate polyester chain members being adhered to at
least one side of the substrate layer.
[0025] In applications wherein the multilayer article of the
present invention is in the form of a film for subsequent use on a
pre-formed substrate, the substrate layer of the multilayer film
helps serve as a reinforcement to facilitate the handling of the
weatherable coating layer which may have relatively little inherent
tensile strength. In other applications, the substrate layer may
incorporate color pigments, metal flakes, etc. to provide special
color effects to the coating layer containing resorcinol arylate
polyester chain members, which may be clear/colorless.
[0026] In one embodiment, the substrate layer is in the form of a
film, in conjunction with the outer layer, forming a protective
film for various end-use applications. The support film may be from
about 1 and 200 mils thick, and in most applications, having a
minimum thickness of 5 mils to ensure good thermoformability and
support properties. In another film embodiment, the support film is
about 5 and 25 mils thick, being capable of withstanding lamination
conditions without adversely affecting its properties.
[0027] In a second embodiment and depending on the polymer resin
used and the intended application of the multi-layer article, the
substrate layer is in the form of a sheet having a thickness of
about 4 to 100 millimeters (mm).
[0028] In yet another embodiment, the substrate layer is a
pre-formed substrate made from a hard, rigid polymer providing a
substrate onto which the coating layer is adhered to. In yet
another embodiment, the substrate layer is a pre-formed substrate
made from glass, ceramics, or a metal such as steel or aluminum,
e.g., an automotive panel. In a fourth embodiment, the substrate
layer is a metal sheet, onto which the weatherable layer containing
resorcinol arylate polyester chain members is adhered to.
[0029] In one embodiment, the support layer may comprise any of a
thermoplastic such as an aromatic polycarbonate, a polyester, a
polyamide, a polyolefin, a thermoplastic polyolefin (TPO), a
polyacrylonitrile (e.g., ABS), acrylic-styrene-acrylonitrile (ASA),
acrylonitrile-(ethylene-polypropylene diamine modified)-styrene
(AES), phenylene ether resins, blends of polyphenylene
ether/polyamide (NORYL GTX.RTM. from General Electric Company),
blends of polycarbonate/polybutylene terephthalate and impact
modifier (XENOY.RTM. resin from General Electric Company), blends
of polycarbonate/PET/PBT, polyamides, phenylene sulfide resins,
polymethylmethacrylate (PMMA), High-impact Polystyrene (HIPS),
polystyrene, poly(vinyl chloride) PVC, a copolyestercarbonate, a
poly(alkylene dicarboxylates), methacrylic ester polymers and
copolymers or blends thereof, which can be melt-extruded into
shaped articles such as films and sheets.
[0030] In another embodiment, the substrate layer is a molded
polymer substrate selected to provide the required engineering
properties, e.g., rigidity, etc., suited to the specific end-use of
the multilayer article. Suitable polymers for the substrate
include, for example, polyvinyl chloride, polycarbonate,
polystyrene, acrylonitrile-butadiene-styrene, polyethylene,
polypropylene, polyethylene terephthalate, nylon, and RIM
urethanes. Polypropylene, for example, when glass filed and foamed
with a blowing agent, is a suitable polymer for the molded
substrate. Acid copolymers of polyethylene such as SURLYN (a
trademark of E.I. DuPont de Nemours) are also suitable. In one
embodiment, the substrate layer is a molded substrate comprising
RIM urethanes. Urethane polymers useful for preparing the molded
substrate are typically prepared by reacting a polyisocyanate with
a compound containing at least two active hydrogen atoms, such as a
polyol, a polyamine, or a polyisocyanate.
[0031] In yet another embodiment, the substrate layer is a
preformed substrate comprising thermoplastic vulcanisates (TPVs),
which are compatible with engineering thermoplastics. Other
examples of the substrate include an unsaturated polyester resin
(UPR), a vinyl ester resin (VE), and/or other thermosettable
resins. Other examples of thermosettable polymers include epoxies,
cyanate esters, diallyl phthalate, acrylics, alkyds,
phenol-formaldehyde such as resoles and novolacs, melamine,
bismaleimides, benzocyclobutanes, hydromethylfurans, and
isocyanates. The substrate may also include parts produced by
various processes such as compression molding of sheet molding
compounds (SMC), bulk molding compounds (BMC), thick molding
compounds (TMC), injection transfer molding, reinforced reaction
injection molding (RRIM), or structural reaction injection molding
(SRIM). Sheet Molding Compound or SMC is generally a highly filled
and glass fiber reinforced, unsaturated polyester/styrene material
made in sheet form. Bulk Molding Compound or BMC is similar to SMC,
but prepared as a bulk material not as sheet. The molding
temperature range for SMC and BMC actually overlaps that for
forming resorcinol arylate polymer resin comprising the coating
layer, which greatly simplifies processing of the multilayer
article.
[0032] In some embodiments, the compound materials are glass
filled, using for examples, long-glass-fibre-reinforced
thermoplastics (LFT) with variable glass contents, or long-fiber
injection (LFI) technology.
[0033] In one embodiment, the substrate layer is a preformed film,
prepared by known liquid casting methods. In another embodiment,
the substrate layer may comprise a liquid cast polymer film formed
from urethane polymers, acrylate polymers, vinyl polymers,
fluoropolymers and blends thereof. Other examples include a cast
film comprising an alloy of an acrylic polymer and polyvinylidene
fluoride.
[0034] In yet another embodiment, the substrate layer is a
pre-fabricated composite structure, e.g., a laminar film structure
that includes a polyimide and a fluoropolymer, a laminar composite
containing a thermoplastic or thermoset polymer layer and a
continuous cellulosic fibrous web, etc. In another embodiment, the
substrate layer is a laminate substrate produced by impregnating a
fibrous substrate with a resin varnish, drying the substrate to
prepare a prepreg, stacking one or more prepregs to a desired
thickness, and finally curing the assembly under heat and pressure
to laminate/mold the substrate layer.
[0035] In another embodiment, the substrate layer is an optically
transparent layer of a material selected from the group consisting
of acrylic polymer, polycarbonate, ionomer, glass, halogenated
polymer, polyolefin, polyester, and polyvinyl butyral. By the term
polycarbonate is meant carbonate polymers possessing recurring
structural units of the formula:
##STR00004##
wherein A is a divalent aromatic radical of the dihydric phenol
employed in the polymer reaction. Suitable aromatic polycarbonate
resins include linear aromatic polycarbonate resins and branched
aromatic polycarbonate resins. Suitable linear aromatic
polycarbonates resins include, for example, bisphenol A
polycarbonate resin. Suitable branched polycarbonates are known and
are made in various embodiments by reacting a polyfunctional
aromatic compound with a dihydric phenol and a carbonate precursor
to form a branched polymer.
[0036] The dihydric phenol which may be employed to provide such
aromatic carbonate polymers are mononuclear or polynuclear aromatic
compounds, containing as functional groups two hydroxy radicals,
each of which may be attached directly to a carbon atom of an
aromatic nucleus. Typical dihydric phenols are:
2,2-bis(4-hydroxyphenyl) propane; hydroquinone; resorcinol;
2,2-bis(4-hydroxyphenyl) pentane; 2,4'-(dihydroxydiphenyl) methane;
bis(2-hydroxyphenyl) methane; bis(4-hydroxyphenyl) methane;
1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; fluorenone
bisphenol, 1,1-bis(4-hydroxyphenyl)ethane; 3,3-bis(4-hydroxyphenyl)
pentane; 2,2'-dihydroxydiphenyl; 2,6-dihydroxynaphthalene;
bis(4-hydroxydiphenyl)sulfone;
bis(3,5-diethyl-4-hydroxyphenyl)sulfone;
2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane;
2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane;
2,4'-dihydroxydiphenyl sulfone; 5'-chloro-2,4'-dihydroxydiphenyl
sulfone; 4,4'-dihydroxydiphenyl ether;
4,4'-dihydroxy-3,3'-dichlorodiphenyl ether, spiro biindane bis
phenol, and the like.
[0037] The term "polyolefin resins" means resins which are
polymerized with an olefin monomer such as propylene, ethylene or
butene and can be selected according to the required performance of
a product such as heat resistance, flexibility and transparency.
The resins may be used alone or in admixture of a plurality of
polyolefin resins in consideration of their crystallinity,
noncrystallinity and elasticity. Examples of polyolefin resins
include polypropylene homopolymers such as isotactic polypropylene,
syndiotactic polypropylene and atactic polypropylene, polyethylene
resins, propylene .alpha.-olefin copolymers or ethylene
.alpha.-olefin copolymers having at least one .alpha.-olefin
monomer such as ethylene, propylene, butene, pentene, hexene,
heptene, octene or 4-methylpentene-1, ethylene vinylacetate
copolymers, ethylene vinylalcohol copolymers, ethylene acrylic acid
copolymers, cyclic polyolefin resins such as those made from
pentadiene and/or derivatives, and the like. In one embodiment, the
polyolefins used include conventional low density polyethylene
(LDPE) made under high pressure; LDPE copolymers incorporating
other .alpha.-olefins polyethylene/vinyl acetate copolymers; linear
low density polyethylenes (LLDPE), which include copolymers of
ethylene with one or more of propylene, butene, hexene, 4-methyl
pentene-1, octene-1, and other unsaturated aliphatic hydrocarbons.
In one embodiment, the .alpha.-olefins are propylene, butene-1,
hexene-1,4-methylpentene-1 and octene-1.
[0038] By the term polyester is meant a thermoset polyester or a
thermoplastic polyester. Examples of thermoplastic polyester
include but not limited to poly(alkylene dicarboxylates),
poly(ethylene terephthalate) (hereinafter sometimes designated
"PET"), poly(1,4-butylene terephthalate) (hereinafter sometimes
designated "PBT"), poly(trimethylene terephthalate) (hereinafter
sometimes designated "PTT"), poly(ethylene naphthalate)
(hereinafter sometimes designated "PEN"), poly(butylene
naphthalate) (hereinafter sometimes designated "PBN"),
poly(cyclohexanedimethanol terephthalate),
poly(cyclohexanedimethanol-co-ethylene terephthalate) (hereinafter
sometimes designated "PETA"), and
poly(1,4-cyclohexanedimethyl-1,4-cyclohexanedicarboxylate)
(hereinafter sometimes designated "PCCD"), poly(alkylene
arenedioates), and polyesters available from renewable agricultural
or other resources, such as vegetable or animal material, biomass,
i.e., formed of polylactic acid.
[0039] By the term polyamide is meant resins such as nylon-6,
nylon-6,6, nylon-6,10, and nylon-6,12.
[0040] Either virgin materials or regrind (or recycled) materials
can be used in the substrate layer. Examples of recycled
engineering plastics for use in the substrate layer include
polycarbonate, polyphenylene ether, many of the polyesters and
polyester blends, polyamides, acetal polymers and copolymers,
thermoplastic polyurethanes, polyarylates which are based on
resorcinol, and the like.
[0041] In some embodiments of the invention, e.g., automotive
applications wherein the multilayer article is used for automotive
body panels including appearance parts, and to achieve sound
damping, it is contemplated that the substrate layer further
includes a foam layer as an adjacent layer as a support or inner
layer. The foam layer helps achieve lower cost, weight reduction
and sound damping with its 10 to 50% density reduction. The foam
may be foamed in place as disclosed in U.S. Pat. No. 5,486,407 to
Noell et. al. It is also contemplated that the substrate layer may
further include, or may be adhered to a cellulosic based material
such as a particleboard, fiberboard, chipboard or plywood. It is
also contemplated that abrasive resistant coatings such as
described in U.S. Pat. No. 5,446,767 may be utilized in conjunction
with the substrate layer.
[0042] In one example of automotive applications, the substrate
layer comprises polycarbonate resin (as a color and adhesive layer)
since polycarbonate adheres to both the coating layer comprising
resorcinol arylate polymer and to another substrate system, e.g.,
thermoset resins systems as SMC and BMC. The thickness of the
multilayer article comprising a polycarbonate substrate layer and
the coating layer is chosen to be sufficient to cover minor surface
blemishes on the SMC/BMC parts resulting in a durable, high grade,
even class "A" finish required for automotive applications. The
high concentration of styrene monomer at elevated temperature and
pressure do not appear to affect the polycarbonate/resorcinol
arylate polymer multilayer film article in any way. Even after long
exposure of the polycarbonate, there does not appear to be any
crazing of the surface due to solvent effects of the styrene
monomer. It is contemplated that similar results are obtainable
with other processes such as RIM, SRIM, TMS, RRIM or RTM and with
non-standard material formulations such as TSN based thermosets.
TSN is Thermoset Noryl, a commercially available product from
General Electric Company.
[0043] The substrate layer may include art-recognized additives
typically known for inclusion in films and sheets, including
pigments, a colorant or decorative material such as metal flakes,
dyes, luminescent compounds, impact modifiers, UV screeners, flame
retardants, fillers, stabilizers, flow aids, ester interchange
inhibitors, adhesion promoting agents such as a bisphenol
derivative, an aminosilane or derivatives, and mold release agents.
Conventional pigments include metallic oxides such as titanium
dioxide, and iron oxide; metal hydroxides; metal flakes such as
aluminum flake; chromates such as lead chromate; sulfides;
sulfates; carbonates; carbon black; silica; talc; china clay;
phthalocyanine blues and greens, organo reds; organo maroons and
other organic pigments and dyes.
[0044] Examples of ultraviolet light absorbers (UVA) include
benzotriazole, benzophenone, triazine, cyanoacrylate,
dibenzoylresorcinol, benzoxazinone and oxanilide based UVA. In
addition to UV absorbers, hindered amine light stabilizers (HALS)
can also be used. Illustrative ultraviolet radiation absorbing
compounds include
2-(benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol,
2-(benzotriazol-2-yl)-4-methylphenol, 2-hydroxy-4-octyloxy
benzophenone, 2-hydroxy-4-methoxybenzophenone,
ethyl-2,2-diphenyl-1-cyanoacrylate,
2'-ethylhexyl-2,2-diphenyl-1-cyanoacrylate,
2-(2'-hydroxy-4'-octyloxy) bis-4,6-(2',4'-dimethylphenyl) triazine,
2-ethyl-2'-ethoxy oxalanide,
bis[2-hydroxy-5-methyl-3-(benzotriazol-2-yl) phenyl]-methane,
bis[2-hydroxy-5-t-octyl-3-(benzotriazol-2-yl) phenyl]methane,
2,2'-(1,4-phenylene) bis[4H-3,1-benzoxazin-4-one], and
2-(2'-hydroxy-4-hexyloxy)-4,6-diphenyltriazine.
[0045] In a preferred embodiment, pigments that are stable at high
temperatures are used, i.e., colorants that do not substantially
degrade or altered at temperatures at or about 350.degree. C.
Examples include Solvent Yellow 93, Solvent Yellow 163, Solvent
Yellow 114/Disperse Yellow 54, Solvent Violet 36, Solvent Violet
13, Solvent Red 195, Solvent Red 179, Solvent Red 135, Solvent
Orange 60, Solvent Green 3, Solvent Blue 97, Solvent Blue 104,
Solvent Blue 104, Solvent Blue 101, Macrolex Yellow E2R, Disperse
Yellow 201, Disperse Red 60, Diaresin Red K, Colorplast Red LB,
Pigment Yellow 183, Pigment Yellow 138, Pigment Yellow 110, Pigment
Violet 29, Pigment Red 209, Pigment Red 209, Pigment Red 202,
Pigment Red 178, Pigment Red 149, Pigment Red 122, Pigment Orange
68, Pigment Green 7, Pigment Green 36, Pigment Blue 60, Pigment
Blue 15:4, Pigment Blue 15:3, Pigment Yellow 53, Pigment Yellow
184, Pigment Yellow 119, Pigment White 6, Pigment Red 101, Pigment
Green 50, Pigment Green 17, Pigment Brown 24, Pigment Blue 29,
Pigment Blue 28, Pigment Black 7, Lead Molybdates, Lead Chromates,
Cerium Sulfides, Cadmium Sulfoselenide, and Cadmium Sulfide.
[0046] In one embodiment of the invention, the amount of colorants
used in the substrate layer may be up to 5 wt. % for opacity. In
another embodiment of the invention, a combination of colorants are
used with some of the colorant being added at low levels for use as
a toner. In a third embodiment, Solvent Yellow 163 is used in an
amount of about 0.35% to provide a yellow colored substrate.
[0047] In another embodiment, in addition to the conventional
pigments and colorants in the art, the substrate layer further
comprises at least a lightfastness compound, a lightfastness
antioxidant, and a lightfastness ozonant.
[0048] Examples of lightfastness compounds include
didodecyl-3,3'-thio dipropionate,
tris(4-tert-butyl-3-hydroxy-2,6-dimethyl benzyl) isocyanurate,
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)
benzene, N,N'-.beta.,.beta.'-naphthalene-4-phenylene diamine, or
4,4'-methylene-bis(dibutyl dithio-carbamate), (6)
2,2,4-trimethyl-1,2-hydroquinoline. Examples of lightfastness
antioxidant include but not limited to: didodecyl-3,3'-thio
dipropionate, tris(4-tert-butyl-3-hydroxy-2,6-dimethyl benzyl)
isocyanurate,
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)
benzene, N,N'-.beta.,.beta.'-naphthalene-4-phenylene diamine,
4,4'-methylene-bis(dibutyl dithio-carbamate),
2,2,4-trimethyl-1,2-hydroquinoline. Examples of lightfast
antiozonant compounds are N,N'-bis(1,4-dimethyl pentyl)-4-phenylene
diamine, 2,4,6-tris-(N-1,4-dimethylpentyl-4-phenylene
diamino)-1,3,5-triazine, 6-ethoxy-1,2-dihydro-2,2,4-trimethyl
quinoline, bis-(1,2,3,6-tetrahydrobenzaldehyde) pentaerythritol
acetal, and the like.
Optional Tie-Layer
[0049] In one embodiment of the multilayer article of the present
invention, at least one tie-layer is used. The tie-layer(s) can be
placed between the coating layer and the substrate layer(s) to
enhance the bond between the coating layer and the substrate, or on
the outer surface of the substrate layer for subsequent adhesion to
another surface. The tielayer(s) may also be placed between
substrate layers to enhance adhesion between layers. Depending on
the applications, the tie-layer can be of a multilayer form, with
each tie-layer comprised of a different material for selective
bonding to either the coating layer, the substrate layer and/or the
surface of the substrate. In one embodiment, the tie-layer is a
co-extruded film of two different heat sensitive adhesive resins
for bonding dissimilar substrates, i.e., the coating layer and the
substrate layer, or the substrate layer of the multilayer article
on the present invention and a base substrate which the multilayer
article is to adhere to.
[0050] The tie-layer ensures both a good adhesion of the coating
layer comprising resorcinol arylate polyester chain members and the
substrate layer(s), or the substrate to which the coating layer or
the multilayer article is adhered. The tie-layer may contain any
polymeric material which improves the interply adhesion between the
layers of the multilayer article, or between the multilayer article
and the substrate it is meant to protect or cover. In one
embodiment, the tie-layer contains a blend of the materials
constituting the substrate layer and the materials comprising
resorcinol arylate polyester chain members.
[0051] In one embodiment, the tie-layer is a compatible blend of:
a) at least one of polycarbonate or a resorcinol arylate containing
resin; and b) at least one of an ester containing resin, a
polyester carbonate containing resin, a resorcinol arylate
containing resin and blends thereof. In another embodiment, the
tie-layer is a polyester selected from the group of: PET, PETG,
PBT, PPT, PEN, PBN, PCT, PCTA, PCTG, PCCD and the like. In yet
another embodiment, the tie-layer is a transparent polyester
selected from the group of PETg, PCT, PCTg, PCCD.
[0052] In another embodiment of a tie-layer, the material is a
compatible blend of polyester and polycarbonate, e.g., transparent
polyester/polycarbonate blends prepared from PETg, PCT, PCTA, PCTg,
and PPCD and BPA polycarbonate. The BPA polycarbonate can be either
linear or branched. In one example, the tie-layer is a blend of
about 20 to 40% PETg and 60 to 80% polycarbonate. In another
example, the tie-layer is a compatible blend of a PCT and BPA
having about 10 to 100% PCT and 0 to 90% polycarbonate. In a third
example, the tie-layer is a compatible blend of a PCTA and BPA
polycarbonate, containing about 10 to 100% PCTA and 0 to 90%
polycarbonate.
[0053] In one embodiment of a compatible blend of: a) a resin
comprising polyester with polycarbonate; and b) a resin comprising
resorcinol arylate units, the transparent polyester/polycarbonate
blends are prepared from PBT, PET, PETg, PCT, PCTA, PCTG. In one
embodiment, the resorcinol arylate resin contains from 70 to 95%
resorcinol arylate units and from 5 to 30% BPA and resorcinol
carbonate units.
[0054] In one example, the tie-layer is a blend containing about 10
to 50% PBT and 50 to 90% a resin comprising of resorcinol arylate
units. In another example, the tie-layer is a compatible blend of a
PET and a resin comprising of resorcinol arylate units, containing
about 10 to 50% PET and 50 to 90% of a resin comprising resorcinol
arylate units. In yet another example, the tie-layer is a
compatible blend of a PETg and a resin comprising resorcinol
arylate units, with about 10 to 50% PETg and 50 to 90% a resin
comprising resorcinol arylate units. In another embodiment, the
tie-layer is a compatible blend of a PCT and a resin comprising
resorcinol arylate units, with about 10 to 50% PCT and 50 to 90% a
resin comprising of resorcinol arylate units. In an embodiment of a
compatible blend of a PCTA and a resin comprising resorcinol
arylate units as a tie-layer, the blend contains about 10 to 50%
PCTA and 50 to 90% a resin comprising of resorcinol arylate units.
In one embodiment of a compatible blend of a PCTG and a resin
comprising resorcinol arylate units, the blend contains about 10 to
50% PCTG and 50 to 90% a resin comprising of resorcinol arylate
units.
[0055] In one embodiment of a tie-layer containing a blend of
materials constituting the substrate layer and the coating layer,
the tie-layer is a transparent blend of a
poly(1,4-cyclohexanedimethyl-1,4-cyclohexanedicarboxylate) ("PCCD")
and polycarbonate. Applicants have found that use of a blend of
PCCD and polycarbonate afford a layer with ductility, and increased
adhesion between the weatherable coating layer and a support layer
of polycarbonate. The blends of PCCD/PC have excellent clarity,
physical and mechanical properties. In one embodiment, the blend
comprises about 20 to 100 wt. % PCCD and about 80 to 0 wt. % of the
polycarbonate.
[0056] In one embodiment of a tie-layer, the tie-layer may comprise
ester side groups such as in polymethyl methacrylate and polymethyl
methacrylate copolymers. The preferred compositions are those with
excellent clarity and melt processability.
[0057] In another embodiment, the tie-layer is a compatible blend
of a resin comprising of a resorcinol arylate and a copolymer
comprising of BPA arylates and BPA carbonates.
[0058] Suitable ITR resins comprising resorcinol arylate blocks are
known; see for example the descriptions and methods for preparation
given in Published Patent Application Nos. EP 1124878 [RD 26354]
and WO0069945 [RD 26310]. In one embodiment of a resin comprising
resorcinol arylate units, the % of resorcinol arylate is from 10 to
90% and the % of BPA and resorcinol carbonates is from 10 to
90%.
[0059] Suitable copolyestercarbonates are comprised of aromatic BPA
polycarbonate units and aromatic polyester units.
[0060] Applicants have found that blends of polyestercarbonate and
ITR are compatible with increased heat deflection temperature
(HDT), ductility, and increased adhesion between the weatherable
coating layer and a support layer of polycarbonate. Applicants have
surprisingly found that only a small portion of these blends afford
a layer with excellent clarity. Furthermore, the clarity of the
polyestercarbonate/ITR tie-layer varies depending on the
concentration of polyestercarbonate employed, the amount of ester
groups in the polyestercarbonate and the amount of resorcinol
arylate groups in the ITR.
[0061] In one embodiment wherein the polyestercarbonate comprises
.about.70 wt % ester or greater and the weight percentage of
polyestercarbonate is greater than about 50% in the tie-layer blend
formulations, the blends have good clarity (less than 30% haze). In
another embodiment, wherein the polyestercarbonate comprises
.about.70 wt % ester or greater and the weight percentage of
polyestercarbonate is greater than about 80% in the tie-layer blend
formulations, the clarity is excellent. In examples wherein the
weight percentage of polyestercarbonate is kept the same, the
tie-layer blends have better clarity with polyestercarbonate having
a high wt. % of the ester group. In embodiments with high
concentration of polyestercarbonate with a high wt. % ester and
with excellent clarity of the tie-layer blends, only one T.sub.g is
detected thus indicating that only one phase exists.
[0062] In one embodiment, the blend comprises 10 to 99 wt. %
polyestercarbonate and about 1 to 90 wt. % of the ITR. In one
embodiment, the blend comprises 80 to 95 wt. % polyestercarbonate
and about 5 to 20 wt. % of the resin comprising of
resorcinolarylate blocks.
[0063] In another embodiment of a tie-layer containing a blend of
materials constituting the support layer and the coating layer, the
tie-layer is a compatible blend of a polyestercarbonate ("PPC") and
polycarbonate. This blend of PPC and polycarbonate provides a
tie-layer with increased heat deflection temperature (HDT),
ductility, increased adhesion between the weatherable coating layer
and a substrate layer of polycarbonate with excellent clarity,
physical and mechanical properties. In one embodiment, the blend
comprises 10 to 100 wt. % PPC and about 0 to 90 wt. % of the
polycarbonate. In one embodiment, the copolyestercarbonates are
comprised of aromatic BPA polycarbonate units and aromatic
polyester units. In embodiments wherein the polyestercarbonate
comprises .about.20 wt % ester or greater and the weight percentage
of polyestercarbonate is greater than about 20%, the tie-layer has
excellent clarity.
[0064] The following table summarizes embodiments of various
tielayers for use in enhancing the adhesion between the coating
layer comprising resorcinol arylate polyester chain members, and a
substrate layer comprising polycarbonate: [0065] a) Polyester as a
tie-layer, with the polyester is preferably a transparent polyester
selected from the group of PETG, PCTG, PCT, PCTA, and PCCD. [0066]
b) A polyestercarbonate as a tie-layer, with the polyestercarbonate
comprising about 10 to 90% ester, with the Iso/Tere ratio of about
0/100 to 100/0. [0067] c) An ITR of lower ester, comprising about 5
to 95% ITR. [0068] d) A PMMA. [0069] e) A blend of ITR and a
polyester, with the polyester selected from the group of PCCD,
PETG, PCTA, PCT, PCTG, PBT, and PET. [0070] f) A blend of
polycarbonate and polyester, with the polyester selected from the
group of PCCD, PETG, PCTA, PCT, PCTG, PBT, and PET. [0071] g) A
blend of polycarbonate and polyestercarbonate, having 10 to 80%
arylate in the blend. [0072] h) A blend of ITR of lower ester, and
a polyestercarbonate.
[0073] In one embodiment wherein the multilayer structure of the
present invention is to adhere to/mold onto a thermoset or metal
substrate, the tie-layer is comprised of a thermoplastic resin
selected from the group of an ethylene/vinyl acetate copolymer
(EVA), a polyester, a copolyester, a copolyamide, a polyurethane
(TPU), a styrene block copolymers (SEBS), a modified SBES, or
blends thereof. Polyurethanes (PU) comprise long polyol chains that
are tied together by shorter hard segments formed by the
diisocyanate and chain extenders if present. Polyol chains are
typically referred to as soft segments, which impart
low-temperature flexibility and room-temperature elastomeric
properties. Generally, the higher the soft segment concentration,
the lower will be the modulus, tensile strength, hardness, while
elongation will increase. Polyols for use as tie-layers in the
multilayer article of the present invention can be generally broken
into three categories: 1) polyether polyols, 2) polyester polyols,
and 3) polyols based on polybutadiene. In one embodiment of the
invention, tie-layers comprising polyols having polyether backbones
are found to have excellent hydrolytic stability especially desired
for automotive applications.
[0074] Examples of commercially available tie-layers include
adhesive films sold as Xiro XAF 36.154 from Adhesive Films, Inc;
polyolefin adhesive films sold as Bemis 6218, Bemis 6329, Bemis
6340 from Bemis Adhesive Films and Coatings; and two-component PU
adhesives Araldite 2040, 2042, and AW8680/HW8685 from Vantico
Inc.
[0075] In one embodiment, the tie-layers are ethylene vinyl acetate
copolymer (EVA), including maleic anhydride functionalized
ethylene-vinyl acetate copolymers. Examples are BYNEL.RTM. CXA
3101.RTM. sold by E. I. du Pont de Nemours and Company, providing
good adhesion and transparency.
[0076] In another embodiment of the invention, the tie-layers are
polyolefins or modified polyolefins, including but not limited to
polyethylene, conventional low-density polyethylene (LDPE), and
linear low-density polyethylenes (LLDPE). In one example, the
tie-layers are based on maleic acid modified waxy ethylene polymers
as described in U.S. Pat. No. 3,892,717 with good adhesion and
transparency. The term "maleic acid compound" comprises maleic
acid, maleic anhydride and the C.sub.1 to C.sub.8 dialkyl esters of
maleic acid. Examples are modified polyolefin with functional group
such as ADMER.RTM. from Mitsui Chemicals. In yet another
embodiment, the tie-layers are blends of a polyolefin component and
high-density polyethylene (HDPE) grafted with an unsaturated fused
ring carboxylic acid anhydride. Examples are anhydride-modified
polyolefins tie-layer adhesives available from Equistar under the
tradename Plexar.RTM..
[0077] The optional tie-layer or layers may include art-recognized
additives including but not limited to pigments, a colorant or
decorative material such as metal flakes, dyes, UV screeners, flame
retardants, fillers, stabilizers, and the like.
[0078] The tie-layer may be from about 0.5 to about 50 mils, and in
one embodiment, having a minimum thickness of about 1 mil to ensure
good thermoformability and adhesion characteristics. The thickness
of the tie-layer depends on the final geometry and shape of the
multi-layer article, and may vary depending on the location within
the article itself.
[0079] The tielayer or tielayers may be used in different physical
form depending on the application process employed. The tielayer or
tielayrs may be in the form of a coextrudable pellet comprising a
single material or blends of materials. The tielayer may be in the
form of a heat activated or thermoset laminate or multilayer
laminate comprised of a single or multiple tielayer materials. In
addition, the tielayer may be in the form of a mat of woven fibers
comprising any one or several of the materials suitable as
tielayers for the adherent surfaces selected.
Uses of the Article of the Present Invention
[0080] Articles of the present invention are useful in a variety of
applications where it is desired to have a high quality weatherable
and/or paint-like appearance on the article, e.g., in applications:
(a) having a need for an adequate life span upon exposure to heat,
sun, chemicals, and/or the like; (b) are scratch resistant, have
luster, and are resistant to marring; (c) having high gloss and
retention of same; (c) having a need for depth of image and color
uniformity; (d) are resistant to gasoline, solvents and/or acid
spotting; (e) having satisfactory hardness and/or abrasion
resistance; (d) having acceptable UV resistance; (e) are resistant
to water and humidity exposure; (f) may be made so as to have
generally consistent coloration throughout at least one color
layer, i.e., throughout the substrate or colored layer; (g) may be
made so that metallizing material/particles can be approximately
uniformly distributed throughout the substrate or color layer(s) of
the article; and (h) may be made using readily available industrial
equipment such as vacuum forming devices, extrusion devices and/or
injection molding machines.
[0081] Examples of such applications including automotive
components, e.g., automotive panels, windshields, side windows,
sunroofs, etc. Other examples include architectural or building
applications, e.g. skylights, or glass windows. In architectural
applications, the multi-layer articles can be used as a
single-sheet having a multilayer structure, or in groups of
multiple sheets. The groups of multi-sheets are sometimes referred
to as walls, as in multi-wall sheet or MWS, with ribs running the
length of the sheets and separating the multilayer articles or
sheets from one another.
[0082] Molded articles or formed parts comprising the multi-layer
articles of the present invention exhibit surprising
weatherability, particularly stability, when exposed to ultraviolet
light for extended periods of time. These articles exhibit the low
loss in gloss, low haze formation, and low color shift measured
using, for example, the CIE 1976 (CIE LAB) color scale, needed for
molded parts used in exterior applications.
[0083] In one embodiment of an automotive application, formed parts
comprising the multi-layer articles of the present invention
exhibit delta E (color shift) values of less than about 3, which is
a level considered as suitable for exterior automotive
applications. In another embodiment of an automotive application
and when exposed to 2500 kilojoules/square meter in a Xenon-arc
weatherometer (SAE J1960), formed parts comprising the multi-layer
articles of the present invention exhibit excellent gloss retention
over time with gloss loss value of less than about 20%. In yet
another embodiment of the invention, the multi-layer articles are
used in automobile fascia applications having DOI ("depth of
image") of at least 80 and superior mar resistance.
[0084] For multi-wall sheets, skylights and architectural glazing
applications, wherein materials with low haze formation are
required when exposed to 10,000 kilojoules/square meter in an Atlas
Ci35a xenon arc weatherometer equipped with borosilicate inner and
outer filters at an irradiance of 0.77 W/m.sup.2 at 340 nm. Typical
operating conditions include: temperatures of black panel
70.degree. C., dry bulb 45.degree. C., wet bulb depression
10.degree. C. The cycle time is 160 minutes (min) light followed by
5 min dark and 15 min dark with water spray.
[0085] In one embodiment, the article is a multilayer structure of:
a) coating layer; b) a first tie-layer; c) substrate layer; d) a
second tie-layer; e) molded substrate or another substrate layer.
In another embodiment, the tie-layer is placed behind the substrate
layer for subsequent adhesion to another substrate, thus forming a
multilayer structure of: a) a coating layer; b) a substrate layer;
c) a tie-layer; d) a base substrate. In a third embodiment, the
optional tie-layer can be part of a structure comprising: a) a
coating layer; b) a tie-layer; and c) a pre-formed substrate. In a
fourth embodiment, the article is in the form of the coating layer
comprising resorcinol arylate polyester chain members being adhered
directly onto a pre-formed substrate. In a fifth embodiment of an
automotive application, the article is a multilayer sheet structure
of: a) a weatherable coating layer; b) a substrate layer; and c)
another layer of the weatherable coating. In a sixth embodiment the
article is a multilayer structure of: a) a coating layer; b) a tie
layer; and c) a molded substrate.
[0086] Depending on the applications and the processing method, and
whether a tie-layer film or multiple tie-layer films are used, a
support layer or multiple support layers are used, whether the
coating layer comprising arylate polyester chain members is in the
form of an extruded film, a molded layer, or a coating, the
multilayer article may be represented as in FIGS. 1(A)-1(D). FIG.
1(A) illustrates a two-layer structure. In this embodiment, the
multilayer article is in the form of a film or a sheet, with a
1.sup.st layer 42 being the weatherable coating layer comprising
resorcinol arylate polyester chain members, and a 2.sup.nd layer 41
being a support layer. This two-layer article may be used as a high
gloss cover/outer layer for exterior trim parts in automotive
applications, such as front fascias and body cladding of cars.
[0087] FIG. 1(B) illustrates a three-layer structure, with the
first layer being the weatherable coating layer 52B comprising
resorcinol arylate polyester chain members, being laminated on the
surface of a tie-layer 52A, which is used to enhance the adhesion
between the coating layer 52B and the substrate layer 51. In a
different embodiment of a three-layer structure (figure not shown),
the weatherable coating layer comprising resorcinol arylate
polyester chain members and the support layer are laminated onto
(or co-extruded with) a tie-layer. This multilayer article may be
subsequently used as an exterior layer to be laminated onto a
substrate base for outdoor/weatherable applications such as
automotive parts.
[0088] FIG. 1(C) illustrates a four-layer structure. In one
embodiment of FIG. 1(C), the weatherable coating layer comprising
resorcinol arylate polyester chain members 73, the tie-layer 72b,
and the substrate layer 72a, are laminated onto an additional
tie-layer 71. This multilayer article may be subsequently used as
an exterior layer to be laminated onto a substrate base for
outdoor/weatherable applications such as automotive parts.
[0089] In another embodiment, the multilayer structure of the
present invention is subsequently masked by a protective film layer
or layers prior to transport to customers. FIG. 4 illustrates a
process to apply a masking layer to the multilayer article of the
present invention.
[0090] In one example, the masking layer is comprised of
polyethylene(s) or blends thereof. For high temperature
applications wherein the multilayer article (including the masking
layer) is used, the masking may be a high-density polyethylene. For
other applications, polypropylenes may be used for the masking
layer. The masking layer can be used to "cover" or "protect" the
weatherable coating layer comprising resorcinol arylate polyester
chain members, covering its gloss surface. It can be used with no
adhesive or with a thin (coating) layer of adhesive to help keep
the masking layer on the weatherable coating layer. In most
applications, the masking layer "clings" to the weatherable coating
layer by the electrostatic charge alone. Leaving a carefully chosen
masking film on the exterior surface of the multilayer article of
the invention, i.e., the exterior of the weatherable coating layer
comprising resorcinol arylate polyester chain members, also helps
protect the surface from damage even during molding. In fact it may
even protect the surface from very minor imperfections found in the
mold surface.
[0091] In another embodiment of the invention, instead of a masking
layer which can be peeled off, a coating layer which complements
the properties of the coating layer resorcinol arylate polyester
chain members is used. The protective coating layer may comprise
acrylate resins or silicone hard coat resins. The coating layer may
be applied by a coating process including but not limited to
fluidizing, dipping, brushing, rolling, spraying, flow-coating or
combinations thereof.
[0092] The multilayer article of the present invention can be
subsequently processed and used in a variety of applications. For
example, the finished multilayer article can be rolled into a roll
for shipping to a processor/molder for various applications, e.g.,
in-mold decoration, or in a hot press. In one application, the
multilayer article in the form of a film is fed from the source
roll into a mold cavity to form shallow contoured parts, with a
different material being injected behind it. In another example, it
is vacuum thermoformed into a desired three-dimensional
configuration. In one example, a multilayer article comprising: a)
weatherable coating comprising resorcinol arylate polyester chain
members, b) an adhesive acrylic as a tie-layer, and c) a PVC film
as a substrate layer, is first placed into a mold as a surface
layer, a moldable polymer such as PVC is next introduced as a
substrate layer, and the surface layer comprising the multilayer
article of the present invention and the PVC substrate are molded
for a time and temperature sufficient to form a shaped article,
with the multilayer article bonded to the outer surface thereof of
the PVC.
Methods for Forming the Multilayer Article
[0093] The multilayer article of the present invention can be
constructed by various processing techniques known in the art
including but not limited to extrusion, co-extrusion, casting,
coating, vacuum deposition, lamination, molding, and combinations
thereof.
[0094] Within co-extrusion, various techniques are employed. In one
embodiment, two or more layers of the multilayer article are
extruded from separate extruders through separate sheet dies into
contact with one another when hot, and then passed through a single
sheet of rollers. In another embodiment, the polymer melts of the
materials constituting the coating layer, the optional tie-layer or
layers, and the substrate layer or layers, are brought together and
into contact with one another through a co-extrusion
adapter/feedblock and then through a single or multi-manifold die.
The adapter/feedblock is constructed such that the melts forming
the separate layers are deposited as adherent layers on the melt of
the center layer. After co-extrusion, the multilayer length of the
melt produced can be formed into desired shapes, solid sheets or
multi-wall panels, in an extrusion die connected downstream. The
melt is then cooled under controlled conditions in known manner by
means of calendering (solid sheet) or vacuum sizing (multi-wall
panel) and subsequently cut into lengths. An annealing oven may be
optionally provided after sizing or calendering for the reduction
of stresses.
[0095] FIG. 2 is an illustration of the co-extrusion process. The
resin comprising resorcinol arylate polyester chain members is
melt-extruded as molten by an extruder (not shown) and fed to feed
block 4 through feed pipe 1 connected to the extruder. A tie-layer
material is extruded as molten by an extruder (not shown), and fed
to one side of the weatherable layer in the feed block 4 through a
feed pipe 2. In the same manner as described above, a material for
use as the substrate layer is fed to the other side of the
tie-layer through a feed pipe 3. In the feed block 4, the molten
polymers meet one another at the junction of three passages to form
a three-layer molten polymer in which the tie-layer serves as the
intermediate layer on one surface of which the weatherable ITR
layer is being laminated and on the other surface of which the
substrate layer is being laminated. The molten polymer is fed to a
single manifold T-die 5, i.e., a single-layer die, connected to the
feed block 4, and then extruded in the form of a film.
[0096] The three-layer film 6 extruded from the T-die 5 is cooled
by a cooling roll 7 and pressed by a pressure roll 8 opposite to
the cooling roll 7. After the film 6 has passed through rolls 9 and
10, the multilayer film is then wound on a winding roll 12.
[0097] The extruding temperature may be suitably set according to
the type of the polymers used. Generally, such a temperature is
generally not less than the softening point of the polymer used.
Other conditions such as polymer extruding speed, cooling roll
temperatures, film drawing speeds, and the like may be set
according to the characteristics of the desired multilayer film and
final applications. The film extruded from the T-die 5, or after
winding roll 12, may be subjected to a surface treatment such as
corona discharge treatment, sputtering treatment, flame treatment,
etc., or a combination of various surface treatment techniques,
prior to being used on a substrate in a final application.
[0098] In one embodiment, wherein the coating layer comprising
resorcinol arylate polyester chain members or a multilayer
structure comprising the coating layer is used directly on a
substrate, conventional molding techniques are used. In an example
of an injection molding process to form the multilayer article of
the present invention, the coating layer comprising resorcinol
arylate polyester chain members, or a multilayer film structure
having a coating layer comprising resorcinol arylate polyester
chain members may be: a) heated and vacuum formed in a separate
forming mold prior to being placed in the injection mold, wherein
the molded polymer substrate is subsequently formed; or b) shaped
and heated by pressure along with a moldable polymer in the
injection mold.
[0099] In an example wherein the coating layer comprising
resorcinol arylate polyester chain members is used directly on a
substrate, the layer comprising resorcinol arylate polyester chain
members is coated on the substrate in a coating process including
but not limited to fluidizing, dipping, brushing, rolling,
spraying, flow-coating or combinations thereof.
[0100] In another example, the multilayer article is prepared by
lamination, after the various free-standing layers in the structure
are prepared by various processes including liquid casting,
extrusion, molding, and stretching operations. According to one
process, one of layer is a sheet, which may be provided directly in
the path of the melted materials exiting the extruder so that
melted flowing material is fed directly into contact with sheet
prior to cooling. At the laminating station, the extrudate in melt
form is contacted with a solid sheet.
[0101] In one embodiment, an extruded coating layer film comprising
resorcinol arylate polyester chain members is thermally laminated
onto a roll of tie-layer or layers of films using a laminator
having heated bottom and top rolls. In another example, the coating
layer is adhesively laminated onto a substrate layer using a
tie-layer film.
[0102] In yet another example of a laminated multilayer structure,
the separate layers, i.e., the weatherable coating layer, the
optional tie-layer(s), and the substrate layer(s), are brought into
contact with one another and then passed through a single set of
rollers for a single sheet line. In another embodiment, the various
diverse layers including the tie-layers, are tacked together and
then heated to a high temperature sufficient to heat and fuse the
films or sheets together, with the optional tie-layer disposed
therebetween the coating layer and the second layer, or as a
backing of the second layer. In one embodiment of the thermofusing
step, appropriate heating temperature control is achieved by
heating with an infrared-heating source. In one embodiment of the
in-line thermofusing process, pressure is applied for 15-75
milliseconds at an increased level, beginning at low levels to
avoid distortion of the component films. The time and amount of
pressure applied will vary according to the polymers used for the
layers, temperatures applied, the thickness of the layers, and
other parameters.
[0103] The multilayer article of the present invention can be
further processed various ways. In one embodiment, it is
thermoformed. Thermoforming comprises simultaneously heating and
forming the multilayer article, e.g., an extruded sheet, into the
desired shape. Once the desired shape has been obtained, the formed
article is cooled below its thermoplastic temperature and removed
from the mold. Thermoforming methods and tools are described in
detail in DuBois and Pribble's "Plastics Mold Engineering
Handbook", Fifth Edition, 1995, pages 468 to 498. Thermoforming
methods may also be utilized as set forth in U.S. Pat. No.
5,601,679 to Mulcahy et al.
[0104] In another embodiment, the mutlilayer article of the present
invention, e.g., in the form of a sheet, may be vacuum formed.
Typically, the vacuum former and surrounding metal framework are
preheated to minimize chill of the sheet. The sheet is placed on a
vacuum box and mounted on the bottom side of the former or platten.
Clamp frames are activated for mechanically holding the sheet in
place. A suitable heat shield, such as aluminum foil, may be
utilized for avoiding heating the surface at selected locations
such as other than a sink portion. The sheet is then exposed to the
thermo-forming ovens. Top and bottom heaters may be used. During
heating, the sheet begins to sag. Once the sheet reaches its proper
forming temperature, the assembly is shuttled to a vacuum forming
box where sink is vacuum formed in a box. The box has a plurality
openings in a mold form for drawing the sheet into mold during the
forming operation. After cooling, the resulting formed sheet is
removed.
[0105] In vacuum molding, the multilayer article, e.g., in the form
of a sheet is placed over a concave mold and heated such as by an
infra-red heater. Vacuum is applied to draw the sheet into place
against the mold cavity. The sheet above may be modified by
combining positive air pressure on top of the extruded sheet with
vacuum from the underside to increase the molding force. In another
process, matched or compression molding, matched male and female
molds or dies are employed and the extruded sheet is formed between
the mechanically compressed molds. Molds are typically made from a
metal having high thermal conductivity such as aluminum.
Optional Surface Enhancement Steps
[0106] In one embodiment of the invention, before the separate
layers of the multilayer article are assembled together according
to any of the methods described above (e.g., thermofusing or
lamination), at least one surface of at least one of the separate
layers is "surface enhanced" according to one of the methods
below.
[0107] The surface of the layer to be surface-enhanced can be the
"inner" surface of the coating layer comprising resorcinol arylate
polyester (ITR) chain members, one or both surfaces of the
tie-layer or layers, one or both surfaces of the substrate layer,
or the "outer" surface of the pre-formed substrate, which surface
is to be coated or covered by the ITR coating layer, or a
multilayer film comprising an ITR coating layer. Surface
modification can enhance the adhesion between the separate layers
of the multilayer article.
[0108] 1. Surface Adhesive Treatment
[0109] In one example of surface enhancing, an adhesive coating is
applied onto at least one surface of any of the layers: the coating
layer comprising arylate polyester chain members, the tie-layer, or
the substrate layer. In another example, an adhesive coating is
applied to the pre-formed substrate onto which the multilayer
article of the present invention is to be adhered.
[0110] The method of applying the adhesive coating includes but not
limited to the followings: spraying a thin layer of the adhesive
layer on at least one surface of any of the layers in the
multilayer article, roll-coating at least one of the surfaces, dip
coating at least one of the film layer as it exits an extruder
line, spraying the adhesive coating on at least one of the
surfaces, roll brush coating, air knife coating, impregnation and
curtain coating, either singly or in combination.
[0111] In one embodiment of the invention, the adhesive coating is
a clear exterior urethane. Adhesive coatings are generally applied
in liquid or semi-liquid form for a thickness of about 25 to 50
microns thick. Besides the desired result of enhanced adhesion, the
use of a clear exterior urethane provide further advantages of
enhanced scratch resistance, enhanced resistance to surface
crazing, and in some applications, aesthetics to increase gloss and
depth of color in appearance.
[0112] 2. Surface Corona Treatment
[0113] Corona surface treatment is a process in which a large, high
frequency electrical field ionizes and excites components of the
air such as oxygen (O.sub.2), creating a corona which contains
positive, negative, and neutral species. These species impact the
electrostatically charged surface of the weatherable coating layer
and/or the substrate layer, causing chemical changes which improve
surface energy and bonding.
[0114] In one embodiment, one of the film layers, i.e., the outer
coating layer or the substrate layer, is passed between two
conductor elements which act as electrodes and a sufficiently high
voltage is applied to enable corona discharges to take place. As a
result of such discharges, the air above the surface of the film
layer becomes ionized and combines with the molecules on the
surface of the film so that polar incorporations are formed in the
essentially nonpolar polymeric matrix. In one embodiment, the
amount of the treatment is about 600 J/m.sup.2 to 12,000 J/m.sup.2.
In another embodiment, it is about 1,200 to 9,000 J/m.sup.2.
[0115] The corona treatment brings about a change to the surface of
the layer, making it wettable and thus resulting in a strong
adhesive bond between the corona-treated layer and a second
surface. In one embodiment, a primer is applied onto the
corona-treated surface to further enhance the adhesions between the
layers of the multilayer article.
[0116] 3. Flame Treatment
[0117] Besides corona treatment, the flame treatment process can be
used to enhance the adhesive-ability of a film layer by making it
wettable. In this process, oxygenated flame is used to create free
oxygen for a short period of time, e.g., a fraction of a second to
a few seconds, on the surface of the film layer of the multilayer
article whose surface is to be enhanced. The free oxygen reacts
with the polymeric surface of the layer and raises the surface
energy level prior to the next operation, wherein the layer is to
be adhered to at least another layer.
[0118] Optimum flaming conditions can be controlled by varying the
various parameters including the gas/air ratio (dependent on the
gas used, town gas, methane, propane, etc.); laminar or turbulent
flow flame; distance of the burner to the film surface. The amount
of the treatment is generally at least 8,000 J/m.sup.2. In one
embodiment, this level is about 8,000 to 200,000 J/m.sup.2. If the
amount of flame treatment is not sufficient, the effect of flame
treatment is insufficient and enhanced adhesion is not certain.
[0119] 4. Plasma Surface Treatment
[0120] This adhesion enhancement method includes the use of
synthetic gaseous plasmas comprising mobile, positively and
negatively charged particles which interact with the surface of the
film layer in the multilayer article that requires enhanced
adhesion. Various types of gaseous plasmas may be used such as
inert gas plasmas of helium, neon, argon or krypton, oxygen and
hydrogen plasmas, and in some applications, organosilane plasmas.
In such treatment, the film layer is passed through an enclosure in
which the gaseous plasma is formed such that at least the exterior
surface film layer to be enhanced is modified by engagement with
the plasma for a predetermined period of time.
[0121] 5. Vacuum Deposition Treatment
[0122] In this process, the surface of the film layer is plasma
treated in a vacuum chamber, for an `atomically clean` surface with
better adhesion properties.
[0123] Adhesion promotion can be achieved using reactive gases.
These produce chemical species and free radicals which react with
or deposit onto the surface, improving the affinity to the
adherrant surface by forming chemical or electrical bonds. In one
embodiment wherein non-reactive, noble gas plasma with heavy ions
is used, the ions cause topographical changes to the surface and
thereby improve mechanical bonding. They can also create surface
radicals through mechanical damage to the atomic structure. These
radicals can then participate in surface reactions and bonding.
[0124] In one embodiment, the vacuum plasma treatment is done at a
temperature ranging between 40-120.degree. C., and in a controlled
environment inside a sealed chamber, which is maintained at a
medium vacuum, usually 13-65 Pa, by the introduction of selected
gases. The plasma gas can be inorganic or organic compounds. As
examples of inorganic gas compounds, oxygen, nitrogen, helium, neon
and argon can be used. Exemplary organic compounds include silanes,
saturated and unsaturated hydrocarbons and aromatics.
[0125] 6. Ionization Radiation
[0126] Ionization tends to occur at higher energies than chemical
dissociation. Typically, for a reactive gas, 104 in 106 molecules
form free radicals whereas only 1 in 106 ionizes. Hence for
reactive gases, the predominant plasma effect is from free
radicals, but with the careful selection of process parameters
using noble gases, ionic effects can predominate. One variation of
vacuum deposition is ionization radiation, in which process the gas
source is energized by an electrical field from DC to microwave
frequencies, ranging from typically 1-5000 W at 500V.
[0127] The ionized gas causes modifications to occur at the film
surface by etching, cross-linking, or film coating, depending on
the treatment gas which is used. Oxygen gas (O.sub.2) has been
found to provide a surface etching phenomena. The use of argon gas
(Ar), helium, or neon has been found to induce cross-linking of the
surface polymer. In one embodiment wherein organic monomers are
used, they provide surface coatings on the polymer film.
[0128] In one embodiment, the film layer surface is first activated
or etched by the use of an organic or inorganic plasma, e.g.,
oxygen gas, after which the surface is contacted with the reactive
monomer gas as the treatment gas for a desired coating layer which
helps with the subsequent adhesion.
[0129] In another embodiment, ionized treatment is first performed
followed by exposing the surface of the film layer to a non-ionized
treatment gas for desired enhanced adhesion properties.
[0130] 7. Chemical Surface Treatment
[0131] This method includes the application of chemical agents such
as hydrochloric acid (HCl), hydro sulfuric acid (H.sub.2SO.sub.4),
or other acids or bases to the surface of film layer to be "etched"
or "surface enhanced" for a predetermined period of time to improve
surface energy and bonding. Depending on whether the film layer to
be etched is the weatherable outer coating layer or the substrate
layer, the chemical etching modifies the outside of the layer for
better acceptance and adhesion of the tie-layer or an adhesion
coating film.
[0132] As mentioned above, these treatment methods may be used with
mirror housings molded from resinous plastic materials or polymers
which may optionally include adhesion promoting agents such as
those described above, although such agents are not absolutely
necessary.
[0133] 8. Super High Frequency (SHF) Radiation Coating
[0134] In one embodiment of the invention, a coating is applied
onto at least one surface of one of the layers in the multilayer
article, the multilayer article is assembled and exposed to
milimetric-wave super high frequency SHF radiation until the
contact surfaces reach different temperatures whereby the coating
can be heated to melting without excessively heating the
weatherable coating layer of the multilayer article. The results
being ensured maximum adhesion therebetween with the physical
properties of the multilayer article being unaffected.
[0135] Gyrotron can be used as a simple and efficient generator of
milimetric waves, in the form of a Gaussian beam, having power in
excess of 10 kilowatts, and at frequencies from 35 to 100 GHz.
[0136] 9. Mechanical Abrasion/Texturing Treatment
[0137] In one embodiment of the invention, the inner surface of the
weatherable coating layer comprising resorcinol arylate chain
members and/or at least one surface of the substrate layer may be
"textured" or "abraded" by mechanical means to enhance the adhesion
of the layers, e.g., between the tie-layer and the support
substrate, in a subsequent process step. The mechanical
texture/abrasion provides a greater contact area between surfaces,
particularly when a tie-layer is used.
[0138] In one embodiment, the mechanical treatment to impart a
textural finish to the surface by embossing or coining, done by
embossing textures on the surface of the film layer while it is
still warm, just rolling off the extrusion line. The film layer
after being extruded by common methods is brought immediately into
contact with a ground steel roll. The finish of the roll will
imprint onto the film surface and control the texture thereof. In
one embodiment, the roll finish has a 5 to about 65 microinch
finish as measured by a commercially available surface analyzer
instrument.
[0139] In a second embodiment, the mechanical treatment is via the
use of a hot embosser bearing an image or pattern, which is to be
transferred to the cooled film layer to be textured. In one
application, the temperature of the hot embosser is between about
125 and 175.degree. C.
[0140] In yet another embodiment, both the contact surface of the
substrate layer (of the multilayer article) and the contact surface
of the substrate to which the multilayer article is adhered are
mechanically textured, with one surface being the negative image of
the other surface, creating crevices on the surface into which the
substrate can flow, resulting in a mechanical interlocking for
excellent bonding between the surfaces.
EXAMPLES
[0141] The following description will illustrate embodiments of the
multilayer articles of the present invention and methods of
manufacturing the multilayer articles of the present invention,
some examples with reference to the attached drawings. Unless
otherwise specified, the weatherable coating layer comprises a
resorcinol arylate-containing block copolyester-carbonate ("ITR")
prepared according to Example 65 of Patent Application
WO0069945.
Example 1
[0142] In one embodiment of the invention, the multilayer article
is formed by having the weatherable coating layer comprising ITR
"coated" onto a substrate via coating method using an
electro-hydrodynamic spray. In Example 1, ITR is dispersed in a
solvent along with a number of additives including but not limited
to absorbents, accelerators, adhesion promoters, adiapates,
anti-blocking agents, anti-foam agents, binders, flame proofing
agents, blowing agents, coloring pigments, flow control agents,
initiators, light stabilizers, optical brighteners, microbicides,
ozone restrictors, thickeners, waxes, and auxiliary processing
materials. The mixture is heated to a flowable state of high
viscosity, with a surface tension of about 10 to 100 dyne/cm. The
heating is done at the last part, i.e., nozzle, of a cone-jet
electro dynamic jetting and dispersion device. The device is
provided with a control electrode to enhance the stability of the
dispersion. The nozzle is heated by means of an electrode. The ITR
in the form of a sprayable and flowable stream, is sprayed onto the
substrate layer, thus forming a weatherable coating layer.
Example 2
[0143] In example 2, ITR is melt-extruded onto a rotating cooled
drum to form a film having a thickness of about 1 mil. The ITR film
is then laminated to a tielayer film from Adhesive Films, Inc. sold
under the trade name Xiro XAF 36.154. The substrate layer is
available in the form of a thermoformable carrier layer, e.g., a
polypropylene copolymer, available from Exxon as Extrel23.
[0144] FIG. 3 is an illustration of example 2. A first roll 10 of
the ITR weatherable coating layer, a second roll 15 of the
tie-layer adhesive film, and a third roll 20 of the substrate layer
are directed to tack station 14 comprising rollers 16, 18 for
tacking together within the nip 24 of tacking station 14. The
multilayer article/joint film 26 is formed at tacking station 14.
The multilayer film continues to a heating station 28 comprising
upper and lower heaters 30 and 32. The film 26 is heated to a
temperature and optionally compressed at a first pressure which is
sufficient for thermofusing the layers together into heated joint
film 34.
[0145] The film is optionally directed to a thermoforming and
bonding station 36, wherein a second pressure in the range of 10 to
100 psi may be applied to remove all air gaps between the layers.
The temperatures sufficient for the thermofusing step in one
embodiment are in the range of about 250 to 450.degree. F., and may
be modified depending on the final application, the type and
thickness of the layers being utilized.
[0146] Of course, more than three different and additional layers,
i.e., additional tie-layers, additional substrate layers in the
form of separate sheets, may be directed to the tacking station 14
along with the coating layer, the tie-layer, and the substrate
layer as illustrated in FIG. 2.
Example 3
[0147] In this example, the adhesive tie-layer roll 15 is omitted
and the surface of the substrate layer opposite the weatherable
coating layer is surface enhanced by being pre-treated by a spray
gun. The spray gun sprays a coating of adhesive onto the surface of
the substrate layer as it rolls off roll 20, and prior to its being
directed to tacking station 14.
[0148] Other surface enhancement techniques can be used or applied
onto the surface of the substrate layer as it rolls off roll 20, or
onto the inner surface of the coating layer as the coating layer
rolls off roll 10. At least one of the surfaces can be treated or
enhanced by any of the following techniques or combinations
thereof: surface corona treatment, flame treatment, plasma surface
treatment, vacuum deposition treatment, ionization radiation,
chemical surface treatment, and mechanical abrasion/texturing
treatment.
Example 4
[0149] In this example 4, resorcinol arylate-containing block
copolyester-carbonate (ITR) is prepared according to Example 48 of
Patent Application WO0069945 for use in the weatherable layer of
the multilayer article. A commercially available polycarbonate
resin from General Electric Company is used for the substrate
layer. The resins are dried overnight to drive out residual
moisture, and then melt-extruded separately as molten. The molten
polymers are fed together to a single-layer die and then extruded
in the form of a film. The extrusion conditions are as listed in
Table 1.
TABLE-US-00001 TABLE 1 Extruder Diameter 2 in. Drying Time
Overnight Drying Temperature 240.degree. F. Extruder Temperature
(.degree. F.) Extruder 1 Extruder 2 Final Extruder Zone 1 470 525
540 Zone 2 490 540 546 Zone 3 500 565 560 Zone 4 515 565 548 Zone 5
530 580 540 Roll Stack Temperature (.degree. F.) 130 230 280
Pressure (psi) 1675 810 Extruder Amps 85 6 Adapter Temperature
(.degree. F.) 550 Line Speed (fps) 14.70
[0150] The resulting two-layer film of 20 mil (4 mil of the
weatherable coating layer comprising ITR and 16 mil of the
polycarbonate substrate layer) is optically transparent with
excellent appearance.
Examples 5-10
[0151] In examples 5-10, various multilayer articles are prepared
and tested. Using a co-extruder with an adapter/feedblock, a
multilayer film is prepared. The film constitutes a layer of
resorcinol arylate polymer prepared according to Example 6 of
published patent application No. EP 1124878 and a layer of
commercially available polycarbonate. This multilayer structure is
adhered to plaques using various tie layers. The tie-layers are
commercially available from Sarna Xiro AG and supplied by Adhesive
Films, Inc., US. The plaques are produced by compression molding of
unsaturated polyester resin (UPR) based SMC with the molding
conditions of 130.degree. C., 1200 psi for 15 minutes. Results of
adhesion test measuring the adhesion of the two-layer film to the
plaques, measured as peel strength in a 90.degree. peel test, are
shown in Table 2.
TABLE-US-00002 TABLE 2 Tie-layer material/Layer(s) Peel strength
Tie-layer used used (lb/in) NONE NONE 3.02 + 1.25 Sarna Xiro XAF
2061 EVA single tie-layer film 13.38 + 3.51 Sarna Xiro Puro L TPU
single tie-layer film 2.82 + 0.35 Sarna Xiro V660 Copolyester/EVA
bilayer 9.09 + 3.14 (Copolyester side in contact with PC substrate
layer) Sarna Xiro V660 EVA/Copolyester bilayer 16.52 + 0.57 (EVA
side in contact with PC substrate layer) Sarna Xiro V660
Copolyester/EVA/Copolyester 10.64 + 0.65 folded over tri-layer
Sarna Xiro 662 Copolyamide/PP/Copolyamide >>20 folded over
tri-layer
Example 11
[0152] Using a co-extruder with an adapter/feedblock, a multilayer
film is prepared. The film constitutes a layer of resorcinol
arylate polymer prepared according to Example 6 of published patent
application No. EP 1124878 and a layer of commercially available
polycarbonate. A laminate film, Xiro XAF 36.154, is placed onto
co-extruded multilayer film structure.
[0153] The multilayer structure is placed into a mold, the mold
closed, and a flowable resin such as polypropylene is injected into
the mold behind the multilayer film. The polypropylene and the
laminate structure are then molded for a sufficient amount of time
and at a sufficient temperature to form a shaped article, with the
coating layer comprising resorcinol arylate polyester chain members
bonded to the surface thereof of the molded substrate.
Examples 12-22
[0154] In these examples, a number of polyestercarbonate and
polycarbonate blends are prepared. The blends are tested for
clarity, Tg, heat distortion temperature HDT, and impact strength
before being further processed as tie-layers in the multilayer
article of the present invention.
[0155] The results of the test are presented in Table 2. Examples
12-22 are blends of either PPC/PCE and ITR, with the weight % of
PPC or PCE is as shown, and ITR resins making up the balance. "PPC"
is a copolyestercarbonate comprising isophthalate and terephthalate
ester units, with 93% isophthalate and 7% terephthalate, and with
the BPA arylates units comprising 80% of the weight. "PCE" is a
copolyestercarbonate comprising isophthalate and terephthalate
ester units, with 50% isophthalate and 50% terephthalate, and with
the BPA arylate units comprising 60% of the weight. The resultant
blends are injection molded at 620.degree. F. into test specimens
1/8'' thick. N.I. is notched izod impact strength measured
according to ASTM D256 at room temperature (RT of 23.degree. C.).
Color (clarity) data is measured using a MacBeth ColorEye 700A
colorimeter. The glass transition temperature Tg is measured at
20.degree. C./min. on the 2.sup.nd heat cycle.
TABLE-US-00003 TABLE 3 Properties of PPC and or PCE/PC blends for
use as tie-layers. PPC PCE T.sub.g, .degree. C., T.sub.g, .degree.
C., HDT .degree. C. NI Ex. wt % wt % L* a* b* % T % H Phase 1 Phase
2 264 psi lb-ft/in 12 0 -- 94.13 -1.63 6.65 85.58 1.12 136.7 --
114.1 4.1 13 25 -- 81.86 -1.26 14.98 60.05 58.19 140 163.6 122 6.6
14 50 -- 77.30 0.33 21.61 52.03 36.88 143.9 163.03 128.2 8 15 75 --
86.15 -0.54 12.39 68.29 19.05 148.8 169.7 138.5 9.9 16 80 -- 89.19
-1.30 11.39 74.56 11.60 150.6 170.01 -- 9.7 17 85 -- 90.93 -1.36
9.68 78.34 6.71 151 171.63 -- 10.4 18 90 -- 93.14 -1.21 6.59 83.28
3.01 -- 174.88 -- 10 19 95 -- 95.19 -0.82 2.95 88.07 0.60 -- 174.86
-- 9.2 20 0 25 76.05 -1.24 17.96 49.96 85.08 139.1 160 119.2 11.5
21 0 50 68.90 1.72 25.62 39.21 63.03 143.6 162.1 126.5 10 22 0 75
77.85 -0.63 17.24 52.95 51.34 146.2 166.89 136 9.6
Examples 23-33
[0156] In examples 23-33, using a co-extruder with an
adapter/feedblock, a multi-layer film is prepared. The film
constitutes a layer of arylate polymer prepared according to
Example 6 of published patent application No. EP 1124878 and
tie-layer(s) prepared from the PPC and PCE-ITR blends of examples
12-22. The multi-layer film is used in a subsequent molding
operation. A substrate is injected onto the tie-layer side of the
multi-layer film to give a multi-layer article comprising: a) a
substrate layer; b) a tie-layer of Examples 12-22, and c) a coating
or top layer of resorcinol arylate polymers. An Instron 90 degree
adhesion peel test is used to test the adhesion between the film
and the injection molding resin. An Instron 180 degree adhesion
peel test is conducted to test the adhesion between the tie-layer
and the weather coating layer.
Example 34
[0157] In this example, multilayer articles in the form of solid
sheets, twin and triple walled panels, and multi-wall sections
(collectively, MWS) are produced by a co-extrusion process, with
the weatherable layer comprising resorcinol arylate-containing
block copolyester-carbonate (ITR) being used as a coating on either
one or both sides of the MWS. The substrate layer or the MWS is a
base sheet of thermoplastic polycarbonate. The ITR resin is
prepared according to Example 48 of Patent Application
WO0069945.
[0158] In some examples, a UV absorber selected from the group of
benzophenones, benzotriazoles, triazines, oxanilides,
cyanoacrylates and cycli imino esters (also referred to
benzoxazinones) is used. In other examples, a hydrophilic coating
as described in U.S. Pat. No. 5,262,475, with low contact angle
with water (10-20 degree) is further coated onto the weatherable
coating layer. These hydrophilic coating are described in the
following references: U.S. Pat. No. 5,262,475.
[0159] The device for co-extruding the multilayer article, i.e.,
the MWS, of the present invention consists of a main with a
degassing facility, a coextrusion adapter (feedblock system), a
coextruder for applying the weatherable coating layer comprising
ITR, a sheet extrusion die, a sizing device, a roller track, a
pull-off device, a device for cutting into lengths (saw), and a
delivery table.
[0160] In the examples, the polycarbonate granules forming the base
sheets are fed to the filling hopper of the main extruder, and the
ITR resin for the weatherable coating layer is fed to that of the
coextruder. Melting and conveying of the respective material are
effected in the respective cylinder/screw plasticizing system. The
two molten materials are brought together in the coextrusion
adapter and formed a composite after leaving the extrusion die and
cooling in the sizing device. The other devices are employed for
the transport, cutting into lengths and deposition of the extruded
sheets.
[0161] The multi-wall sheets are subject to the Table Abrasion test
(ASTM D1044 with CS-10F wheels) using 100 cycles, a chemical
resistance test in which the sheets are cleansed with a cheesecloth
soaked in methyl ethyl ketone (MEK), and a UV resistance test in
which the sheets are weathered in a Xenon Arc weather-o-meter using
a modified SAE J1960 protocol, with the change in haze and gloss
being recorded before and after.
Example 35-37
[0162] Using a co-extruder with an adapter/feedblock, a multilayer
film is prepared. The film constitutes a layer of resorcinol
arylate polymer prepared according to Example 6 of published patent
application No. EP 1124878 and a layer of commercially available
polycarbonate. A multilayer article comprising the multilayer film
is prepared over SMC or BMC, with the following results:
TABLE-US-00004 Example Samples/Conditions Results 35
SOLLX/commercial SMC Good surface and adhesion 36 SOLLX/TSN Good
surface, poor adhesion 37 SOLLX/commercial SMC Very good surface,
excellent adhesion
[0163] The samples are prepared by compression molding using the
multilayer film over either SMC or BMC. One sample is made with
Thermosetting Noryl (TSN) based BMC. TSN is a commercially
available material from General Electric Company. The samples are
formed and held in a heated mold until the reaction is deemed
completed, but at a mold temperature (150-180.degree. F.) that does
not soften the coating layer comprising resorcinol arylate polymer
sufficiently to degrade the surface appearance. Cycle times and
pressure profiles varied greatly, since different presses and molds
are used in each case.
Example 38
[0164] Using a co-extruder with an adapter/feedblock, a three-layer
sheet is prepared. The sheet constitutes two outer film layers of
resorcinol arylate polymer prepared according to Example 6 of
published patent application No. EP 1124878, and an inner layer
sheet having a thickness of 3 mm comprising a commercially
available polycarbonate.
[0165] The sheet is further subject to vacuum forming by first
being dried for four hours at 125.degree. C. It is next heated to
reach 240.degree. C. surface temperature for about 15 seconds. It
is observed that there is no sagging in the sheet due to air
support. Vacuum forming is next for about 3 to 5 seconds into a
desired shape, with the following properties being measured:
vacuum-formability, taber abrasion, impact behaviour, cap-layer
thickness after forming, weathering performance, and optical
inspection.
[0166] It is observed that the sheet having outer layers of
resorcinol arylate polymer forms better than sheet having outer
layers of polycarbonate film. Additionally, the surface stretching
after forming is very uniform with no tearing occurs. There is no
delamination at any point. Furthermore, the impact strength is the
same or as expected of a similar sheet having polycarbonate as
caplayers.
[0167] An article similarly formed as in this example 38 can be
used in a number of different applications, including architectural
applications as windows, skylights, and partitions. The article can
also be used in automotive applications, including windows for
transportation vehicles such as cars, trucks, boats, and
trains.
Example 39
[0168] In the example, the multilayer article assembly comprised a
layer of copolyestercarbonate film and a layer of polycarbonate
film. The copolyestercarbonate film comprised a
copolyestercarbonate with arylate structural units derived from
unsubstituted resorcinol, isophthalic acid, and terephthalic acid,
and carbonate structural units derived from bisphenol A. The
polycarbonate film comprised bisphenol A polycarbonate. The
abbreviation "PU" means polyurethane. The abbreviation "SMC" means
sheet molding compound. The abbreviation "TSN" means thermoset
NORYL, a material obtained from General Electric Plastics. TSN
comprised a major amount of a poly(2,6-dimethylene-1,4-phenylene
ether) of low intrinsic viscosity and a minor amount of a
crosslinkable acrylic ester monomer, along with various amounts of
fillers, additives, and curing agents.
Examples 40-42
[0169] Laminates of copolyestercarbonate-polycarbonate film
assembly onto e-coated steel with PU adhesive tie-layer: The
two-component PU tie-layer adhesives, ARALDITE 2040, 2042, and
AW8680/HW8685, were obtained from Vantico Inc. (formerly Ciba
Performance Specialty Polymers). Both ARALDITE 2040 and 2042
contained polymeric methylene diphenyl diisocyanate and primarily
polyether polyols. ARALDITE 2042 contained only polyether polyols.
E-coated steel test panels were obtained from ACT Laboratories (ACT
# APR 31330). The e-coated metal was electro-zinc galvanized steel
typically used for automotive body panels which was cleaned,
phosphate treated, and finally e-coated with PPG e-coating
formulation (type ED5100). A copolyestercarbonate-polycarbonate
film assembly was prepared by coextruding a 10 mil thick clear
copolyestercarbonate film with a 20 mil thick pigmented,
cranberry-colored polycarbonate layer containing metal flakes for
metallic effects. The PU adhesive components were thoroughly mixed
in paste form and uniformly applied to the dried e-coated metal
substrates in a thin layer by using an application gun and attached
static mixer pipe. A copolyestercarbonate-polycarbonate film
assembly, which had been surface-washed with deionized water and
oven dried, was then put on top of the adhesive with the
polycarbonate film side in contact with the adhesive. This combined
assembly was placed in a Carver press and heated on both sides
under 689 kilopascals pressure for 10 to 30 minutes at temperatures
given in the Table. The copolyestercarbonate-polycarbonate film
assembly adhered well to the substrates. Samples were cut into
one-inch wide stripes and tested for adhesion using a 90-degree
peel test with a crosshead separation speed of one inch per minute
using an Instron testing device (Model 4505). The adhesion strength
of the tie layer with copolyestercarbonate-polycarbonate film
assembly and metal substrate was measured by the peel force in
Newtons per meter (N/m). The adhesion results are shown in Table
4.
TABLE-US-00005 TABLE 4 Molding Peel Molding T time - force Failure
Example Adhesive (.degree. C.) min. (N/m) mode 40 ARALDITE 100 30
5779 Cohesive 2040 PU 41 ARALDITE 100 10 4903 Interfacial 2042
PU/steel 42 AW8680/HW 60 90 4028 Interfacial 8685 PC/PU
[0170] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the metal
substrate was found to be excellent.
Examples 43-44
[0171] Laminates of copolyestercarbonate-polycarbonate film
assembly onto cleaned and chemical conversion coated steel with PU
tie-layer: A laminate was prepared according to Examples 1-3 with
copolyestercarbonate-polycarbonate film assembly onto a cold-roll
steel test panel (cleaning and chemical conversion pretreated)
obtained from ACT Laboratories (ACT # APR 32488) using PU
adhesives. The adhesion results are shown in Table 5.
TABLE-US-00006 TABLE 5 Molding Molding Peel temp. time force
Failure Example Adhesive (.degree. C.) (min.) (N/m) mode 43
ARALDITE 100 30 2802 Interfacial 2042 PU/steel 44 ARALDITE 100 10
2101 Interfacial 2040 PU/steel
[0172] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the metal
substrate was found to be excellent.
Examples 45-46
[0173] Laminates of copolyestercarbonate-polycarbonate film
assembly onto SMC with PU tie-layer: Smooth surface, class "A" SMC
was received from the Budd Company (Budd product #DSM-971) and
comprised unsaturated polyester resin with curing agents and
fillers. SMC prepreg was cured into a large panel at 149.degree. C.
and 8273 kilopascals for 90 seconds. Test panels of dimension
four-inches-by-six-inches were cut from the molded SMC panels and
were cleaned with deionized water and dried. A laminate was
prepared according to Examples 1-3 with
copolyestercarbonate-polycarbonate film assembly onto the SMC test
panel using PU adhesives. The adhesion results are shown in Table
6.
TABLE-US-00007 TABLE 6 Molding Molding Peel temp. time force
Failure Example Adhesive (.degree. C.) (min.) (N/m) mode 45
ARALDITE 100 30 5954 Interfacial 2042 PU/SMC 46 ARALDITE 100 10
7005 Cohesive 2040 PU
[0174] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the cured
thermoset substrate was found to be excellent.
Examples 47-48
[0175] Laminates of copolyestercarbonate-polycarbonate film
assembly onto TSN with PU tie-layer: A TSN formulation was cured
into a twelve-inch-by-twelve-inch panel at 150.degree. C. for 4
minutes under 6894 kilopascals pressure. Test panels of
four-inch-by-six-inch dimensions were cut from the molded TSN
panels and were cleaned with deionized water and dried. A laminate
was prepared according to Examples 1-3 with
copolyestercarbonate-polycarbonate film assembly onto the TSN test
panel using PU adhesives. The adhesion results are shown in Table
7.
TABLE-US-00008 TABLE 7 Molding Molding Peel temp. time force
Failure Example Adhesive (.degree. C.) (min.) (N/m) mode 47
ARALDITE 100 30 2802 Interfacial 2042 PU/TSN 48 ARALDITE 100 10
2627 Interfacial 2040 PU/TSN
[0176] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the cured
thermoset substrate was found to be excellent.
Examples 49-52
[0177] Laminates of copolyestercarbonate-polycarbonate film
assembly onto e-coated steel and chemical conversion coated steel:
Aliphatic thermoplastic polyurethane film, grades PE393 and PE399,
of 50 mil thickness were obtained from JPS Elastomerics Corp.
DUREFLEX A4700 polyurethane film of 50 mil thickness was obtained
from Deerfield Urethane, Inc. Each type of PU film was laminated to
a copolyestercarbonate-polycarbonate film assembly at 110.degree.
C. and 344 kilopascals for 2 minutes using a hot press. E-coated
steel test panels were obtained from ACT Laboratories (ACT #
APR26782). The e-coated metal was cold-roll steel which was
cleaned, phosphate treated, and finally e-coated with PPG e-coating
formulation. The copolyestercarbonate-polycarbonate film assembly
with PU laminated to the polycarbonate side was then put on top of
the e-coated steel substrate with PU film layer in contact with the
metal surface. Each assembly was placed in a Carver press and
heated on both sides under 689 kilopascals pressure and 127.degree.
C. for 10 minutes. The copolyestercarbonate-polycarbonate film
assembly adhered well to the substrates. The adhesion strength of
the tie layer with copolyestercarbonate-polycarbonate film assembly
and metal substrate was measured by the peel force.
TABLE-US-00009 TABLE 8 PU Peel adhesive force Failure Example
Substrate film (N/m) mode 49 e-coated steel PE393 13,414
Interfacial PU/steel 50 e-coated steel PE399 24,902 Interfacial
PU/steel 51 e-coated steel A4700 20,944 Interfacial PU/steel 52
pretreated steel A4700 2504 Interfacial PU/steel
[0178] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the metal
substrate was found to be excellent.
Examples 53-54
[0179] Laminates of the multilayer article of the present
invention, e.g., the copolyestercarbonate-polycarbonate film
assembly, onto e-coated Aluminum and chemical conversion coated
Aluminum: E-coated aluminum test panels were obtained from ACT
Laboratories (ACT # APR 41719). E-coated aluminum panels of the
type used for automotive body panels had been cleaned, phosphate
treated, and finally e-coated with PPG lead-free e-coating
formulation (type ED6100H). Pretreated aluminum panels (cleaned and
chemical conversion pretreated using Henkel immersion phosphate)
were also obtained from ACT Laboratories (ACT # APR 41718).
Laminates were prepared according to Examples 10-13 (except as
noted) with copolyestercarbonate-polycarbonate film assembly onto
an aluminum substrate using the PU film adhesive DUREFLEX A4700 of
25 mil thickness. The adhesion results are summarized in Table
9.
TABLE-US-00010 TABLE 9 Molding Mold Peel temp. press. force Failure
Example Substrate (.degree. C.) (kPa) (N/m) mode 53 e-coated Al 121
172 26,180 Interfacial PU/Al & PU/PC 54 pretreated Al 127 689
7968 Interfacial PU/Al
[0180] In each example the adhesion strength of the
copolyestercarbonate-polycarbonate film assembly to the metal
substrate was found to be excellent.
Examples
Adhesion Environmental Stability Tests
[0181] Adhesion environmental stability data for laminates of
multilayer article of the present invention, the
copolyestercarbonate-polycarbonate film assembly, onto e-coated
steel and SMC: Multilayer structures of
copolyestercarbonate-polycarbonate film assembly over e-coated
steel or SMC or e-coated aluminum, the same as those in examples
1-2 and 10-12, examples 6-7, and example 14, respectively, were
prepared and subjected to a full cycle crack resistance test under
varying conditions of temperature and humidity. Each full cycle
involved holding the sample successively for 24 hours at 84.degree.
C., 16 hours at 38.degree. C. and 98% relative humidity, 6 hours at
minus 29.degree. C., and 2 hours at 23.degree. C. Each sample was
subjected to 15 cycles. All samples were visually inspected after
the full cycle crack test and were found to have no macroscopic
delamination or other film-related failure. These
four-inches-by-six-inches cycle cracked samples were then cut into
one-inch-by-six-inches test specimen for 90-degree peel test at one
inch per minute cross-head separation speed. The results are
summarized in Table 10.
TABLE-US-00011 TABLE 10 Peel strength Adhesive/ after cycle
Thickness of crack test Peel failure Ex. Substrate adhesive (N/m)
mode 55 e-coated steel ARALDITE 2040 5779 Cohesive PU 5 mil and
interfacial PC/PU 56 e-coated steel ARALDITE 2042 175-525
Interfacial 5 mil PC/PU 57 SMC ARALDITE 2040 3520 Interfacial 20
mil PC/PU 58 SMC ARALDITE 2042 350 Interfacial 20 mil SMC/PU 59
e-coated steel PE393 50 mil film 17,845 -- 60 e-coated steel PE399
50 mil film 21,102 -- 61 e-coated steel A4700 50 mil film 28,387 --
62 e-coated Al A4700 25 mil film 24,201 --
[0182] The results showed that adhesion provided to multilayer film
assembly and e-coated steel by ARALDITE 2040 and the three types of
polyurethane film is environmentally stable, and adhesion strength
remains excellent after the full cycle crack test protocol.
Although the invention is not dependent upon any theory of action,
this excellent adhesion stability may be due to the hydrolytic
stability and/or low modulus of ARALDITE 2040 and of the three
types of polyurethane film which allows them to accommodate any CTE
mismatch between copolyestercarbonate-polycarbonate film assembly
and low CTE substrates.
* * * * *